ABSTRACT
Introduction: Sepsis is a vitally serious disease leading to high mortality. Nucleated red blood cells (NRBCs) are present in some noninfectious diseases, but the relationship between NRBCs and sepsis in children remains unknown. The purpose of this study was to compare the clinical characteristics and outcomes of sepsis with positive NRBCs and negative NRBCs in children, and to further explore whether the count of NRBCs has a relationship with the severity of sepsis. Methods: We enrolled children with sepsis who were admitted to the Children's Hospital of Chongqing Medical University between January 2020 and December 2022. The children's clinical data, laboratory data and outcomes were recorded and analyzed. Results: One hundred and fifteen children met the inclusion criteria in our study. Compared to negative NRBCs patients, the C-reactive protein, alanine transaminase, urea nitrogen values, mortality rate and length of hospitalization were found to be significantly increased, while platelet counts, and hemoglobin were significantly decreased in sepsis patients with positive NRBC (P < 0.05). Receiver operating characteristic (ROC) curves analysis showed that the optimal cutoff value of the NRBC count in the diagnosis of severe sepsis was 3, with a sensitivity of 87.5% and specificity of 94.9%. The area under the ROC curve was 0.877 (95% CI: 0.798-0.957). Discussion: These findings demonstrated that NRBC count has the potential to be a biomarker for the diagnosis of sepsis in children, especially an NRBC count greater than 3, which may predict the severity and poor prognosis in children suffering from sepsis.
Subject(s)
Erythroblasts , Sepsis , Humans , Child , Biomarkers , C-Reactive Protein , Hospitalization , Sepsis/diagnosisABSTRACT
OBJECTIVES: Bacterial pneumonia is a common serious infectious disease with high morbidity and mortality. Prokineticin 2 (PK2) has recently been identified as a novel immunomodulator in a variety of diseases; however, its role in bacterial pneumonia remains unclear. METHODS: The levels of PK2 were measured and analyzed in patients with pneumonia and healthy controls. The effects of PK2 on the host response to pneumonia were evaluated by in vivo animal experiments and in vitro cell experiments. RESULTS: PK2 levels dramatically decreased in patients with pneumonia compared with healthy controls, and PK2 levels were lower in patients with severe pneumonia than in pneumonia. In a mouse model of bacterial pneumonia, transtracheal administration of recombinant PK2 significantly alleviated lung injury and improved the survival, which was associated with increased host's bacterial clearance capacity, as manifested by decreased pulmonary bacterial loads. PK2 enhanced the chemotaxis, phagocytosis, and killing ability of macrophages, whereas the protective efficacy of PK2 was abolished after macrophage depletion. CONCLUSION: Impaired alveolar macrophage function caused by decreased PK2 is a new endogenous cause of the occurrence and development of bacterial pneumonia. The administration of recombinant PK2 may be a potential adjuvant therapy for bacterial pneumonia.
Subject(s)
Gastrointestinal Hormones , Neuropeptides , Pneumonia, Bacterial , Mice , Animals , Neuropeptides/therapeutic use , Macrophages , Pneumonia, Bacterial/drug therapy , Anti-Bacterial AgentsABSTRACT
Silver nanoparticles (Ag-NPs) were found to be responsible for nitrous oxide (N2O) generation; however, the mechanism of Ag-NP induced N2O production remains controversial and needs to be elucidated. In this study, chronic Ag-NP exposure experiments were conducted in five independent sequencing batch biofilm reactors to systematically assess the effects of Ag-NPs on N2O emission. The results indicated that a low dose of Ag-NPs (< 1 mg/L) slightly suppressed N2O generation by less than 22.99% compared with the no-Ag-NP control method. In contrast, a high dose (5 mg/L) of Ag-NPs stimulated N2O emission by 67.54%. ICP-MS and SEM-EDS together revealed that high Ag-NP content accumulated on the biofilm surface when exposed to 5 mg/L Ag-NPs. N2O and DO microelectrodes, as well as N2O isotopic composition analyses, further demonstrated that the accumulated Ag-NPs construct the anaerobic zone in the biofilm, which is the primary factor for the stimulation of the nitrite reduction pathway to release N2O. A metagenomic analysis further attributed the higher N2O emissions under exposure to a high dose of Ag-NPs to the higher relative abundance of narB and nirK genes (i.e. 1.52- and 1.29-fold higher, respectively). These findings collectively suggest that chronic exposure to high doses of Ag-NPs could enhance N2O emissions by forming anaerobic micro-environments in biofilms.
Subject(s)
Metal Nanoparticles , Silver , Silver/pharmacology , Denitrification , Nitrous Oxide/metabolism , Nitrites , AnaerobiosisABSTRACT
OBJECTIVES: Dementia and seizures often co-exist, but the association between these two disorders is not well established. Therefore, this systematic review and meta-analysis aimed to clarify the relationship between seizures and dementia. METHODS: The PubMed, EMBASE, CBM, and CNKI databases were used to search for relevant publications from inception to August 25, 2021. Data extraction was performed by two authors independently. The random-effects model was adopted to evaluate the pooled estimates. RESULTS: Two nested case-control studies and 18 cohort studies were included in the meta-analysis. Seizures were associated with the development of dementia and Alzheimer's disease (AD), and the pooled relative risk (RR) was 2.51 [95% confidence intervals (CI) = 1.87-3.36, p < 0.001] and 1.61 (95% CI = 1.42-1.82, p < 0.001), respectively. Pooled RR estimating the effect of dementia on seizures risk was 3.68 (95% CI = 3.05-4.44, p < 0.001). In addition, the pooled effect size of dementia on epilepsy risk was 3.02 (95% CI = 2.16-4.23, p < 0.001). The subgroup analyses suggested that vascular risk factors could confound the associations between these two disorders. Seizures might independently and significantly increase the risk of dementia, and in turn, dementia might predispose an individual to a higher risk of seizures. CONCLUSIONS: These results suggested that dementia and seizures share common pathogenesis and might be treated with similar preventive treatment measures. Vascular changes in patients with dementia or seizures should also be examined.
Subject(s)
Alzheimer Disease , Alzheimer Disease/epidemiology , Case-Control Studies , Cohort Studies , Humans , Risk Factors , Seizures/epidemiology , Seizures/etiologyABSTRACT
OBJECTIVES: Sepsis remains a highly lethal disease, whereas the precise reasons for death remain poorly understood. Prokineticin2 is a secreted protein that regulates diverse biological processes. Whether prokineticin2 is beneficial or deleterious to sepsis and the underlying mechanisms remain unknown. DESIGN: Prospective randomized animal investigation and in vitro studies. SETTING: Research laboratory at a medical university hospital. SUBJECTS: Prokineticin2 deficiency and wild-type C57BL/6 mice were used for in vivo studies; sepsis patients by Sepsis-3 definitions, patient controls, and healthy controls were used to obtain blood for in vitro studies. INTERVENTIONS: Prokineticin2 concentrations were measured and analyzed in human septic patients, patient controls, and healthy individuals. The effects of prokineticin2 on sepsis-related survival, bacterial burden, organ injury, and inflammation were assessed in an animal model of cecal ligation and puncture-induced polymicrobial sepsis. In vitro cell models were also used to study the role of prokineticin2 on antibacterial response of macrophages. MEASUREMENTS AND MAIN RESULTS: Prokineticin2 concentration is dramatically decreased in the patients with sepsis and septic shock compared with those of patient controls and healthy controls. Furthermore, the prokineticin2 concentration in these patients died of sepsis or septic shock is significantly lower than those survival patients with sepsis or septic shock, indicating the potential value of prokineticin2 in the diagnosis of sepsis and septic shock, as well as the potential value in predicting mortality in adult patients with sepsis and septic shock. In animal model, recombinant prokineticin2 administration protected against sepsis-related deaths in both heterozygous prokineticin2 deficient mice and wild-type mice and alleviated sepsis-induced multiple organ damage. In in vitro cell models, prokineticin2 enhanced the phagocytic and bactericidal functions of macrophage through signal transducers and activators of transcription 3 pathway which could be abolished by signal transducers and activators of transcription 3 inhibitors S3I-201. Depletion of macrophages reversed prokineticin2-mediated protection against polymicrobial sepsis. CONCLUSIONS: This study elucidated a previously unrecognized role of prokineticin2 in clinical diagnosis and treatment of sepsis. The proof-of-concept study determined a central role of prokineticin2 in alleviating sepsis-induced death by regulation of macrophage function, which presents a new strategy for sepsis immunotherapy.
Subject(s)
Sepsis , Shock, Septic , Animals , Disease Models, Animal , Humans , Macrophages , Mice , Mice, Inbred C57BL , Prospective StudiesABSTRACT
Toll-like receptor 7 (TLR7) is a sensor of microbial ssRNA that participates in the immune response process in many diseases. We herein sought to establish the role of TLR7 in Pseudomonas aeruginosa pneumonia. Pneumonia model was created by intratracheally injecting Pseudomonas aeruginosa and the effects of TLR7 on survival, bacterial burden, lung pathology, cytokine and chemokine production, and pulmonary leukocyte recruitment were measured after Pseudomonas aeruginosa challenge. TLR7 expression was significantly elevated in WT mice after Pseudomonas aeruginosa infection. TLR7-/- mice demonstrated enhanced survival, bacterial clearance, leukocyte infiltration, and macrophages phagocytic activity, and decreased pathology and capillary leakage. Besides, improved survival and bacterial clearance were observed in WT mice treated with TLR7 antagonist IRS661. More importantly, lack of TLR7 suppressed pro-inflammatory cytokine production and induced anti-inflammatory cytokine production in mice lungs. Finally, neutralized IL-10 damaged the bacterial clearance ability of TLR7 deficient mice, leading to decreased survival. Collectively, absence of TLR7 provided protective effects during Pseudomonas aeruginosa pneumonia and suggested that TLR7 could act as a novel immune target to treat clinical cases with Pseudomonas aeruginosa pneumonia.
Subject(s)
Interleukin-10/metabolism , Lung/immunology , Macrophages, Alveolar/immunology , Membrane Glycoproteins/deficiency , Pseudomonas Infections/prevention & control , Pseudomonas aeruginosa/immunology , Toll-Like Receptor 7/deficiency , Animals , Disease Models, Animal , Lung/metabolism , Lung/pathology , Macrophages, Alveolar/drug effects , Membrane Glycoproteins/immunology , Membrane Glycoproteins/metabolism , Mice , Mice, Knockout , Pseudomonas Infections/immunology , Pseudomonas Infections/metabolism , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/isolation & purification , Pseudomonas aeruginosa/metabolism , Survival Rate , Toll-Like Receptor 7/immunology , Toll-Like Receptor 7/metabolismABSTRACT
Interferon-γ (IFN-γ) is traditionally regarded as a proinflammatory cytokine by virtue of its strong macrophage activating potential and its association with Th1 driven immune responses. NOD1 and NOD2 are cytoplasmic receptors that can initiate the initial immune response by sensing bacterial components or danger signals. In this study, we investigated the immunopathological roles of IFN-γ and NOD1, 2 ligands iE-DAP/MDP on the activation of fibroblast-like synoviocytes (FLS) in RA. FLS constitutively express functional NOD1 and NOD2, and the gene and protein expression of NOD1 and NOD2 could be enhanced by the treatment with IFN-γ. The synergistic effect was observed in the combined treatment of IFN-γ and NOD1 ligand iE-DAP or NOD2 ligand MDP on the release of CCL5, CXCL9 and CXCL10 from FLS, and its effect was in a dose-dependent manner. The co-stimulation which IFN-γ combined with iE-DAP/MDP could abolish the inhibition of CXCL8 level by IFN-γ alone. Further investigations showed that synergistic effects on the production of CCL5, CXCL9 and CXCL10 in FLS stimulated by IFN-γ and iE-DAP/MDP were differentially regulated by intracellular activation of NF-κB, p38MAPK and ERK pathways. In conclusion, our data confirmed the inflammatory effect of IFN-γ and iE-DAP/MDP on human FLS for the first time and therefore provided a new insight into the IFN-γ combined with NOD1 or NOD2 activated immunopathological mechanisms mediated by distinct intracellular signal transduction in joint inflammation of RA.
ABSTRACT
BACKGROUND: Infections are leading causes of morbidity and mortality in neonates and may also have severe long-term consequences. As early diagnosis of neonatal sepsis improves prognosis, identification of new or complementary biomarkers is of great importance. In this study, we have evaluated the diagnostic value of progranulin (PGRN) in early-onset neonatal sepsis (EOS) and compare its effectiveness with other commonly used biomarkers, such as procalcitonin (PCT) and C-reactive protein (CRP). METHODS: A total of 121 infants with gestational age of >34 weeks admitted with suspected EOS were included in this study. Before initiating therapy, blood samples for whole blood count, CRP, PCT and PGRN were obtained from all neonates. Receiver-operating characteristic (ROC) curve and multivariate logistic regression analyses were performed. RESULTS: Serum PGRN level of infected group was significantly higher than uninfected group (median 47.72 vs. 37.86 ng/ml, respectively; Mann-Whitney p < 0.0001). The ROC area under the curve (AUC) was 0.786 [95% confidence interval (CI) 0.706-0.867; p < 0.0001] for PGRN, 0.699 (95% CI 0.601-0.797; p = 0.0001) for age adjusted PCT, and 0.673 (95% CI 0.573-0.773; p = 0.0007) for CRP. With a cut-off value of 37.89 ng/ml, the diagnostic sensitivity and negative predictive value of PGRN were 94.34% and 91.7%, respectively. PGRN could significantly predict EOS independently of PCT (p < 0.0001), and the combined use of PGRN and PCT could significantly improve diagnostic performance for EOS (0.806; 95% CI 0.73-0.88; p < 0.0001), with a specificity of 89.06% and a positive predictive value of 81.10%. CONCLUSIONS: PGRN may be used as a promising biomarker for the diagnosis of EOS, and the combined use of PGRN and PCT could improve the diagnosis of sepsis.
Subject(s)
Biomarkers/blood , Neonatal Sepsis/blood , Neonatal Sepsis/diagnosis , Progranulins/blood , C-Reactive Protein/metabolism , Calcitonin/blood , Early Diagnosis , Female , Gestational Age , Humans , Infant, Newborn , Male , Neonatal Sepsis/metabolism , Neonatal Sepsis/pathology , Procalcitonin/blood , Prognosis , Prospective Studies , ROC CurveABSTRACT
A forward osmotic membrane bioreactor for sludge anaerobic digestion (ad-OMBR) could realize high-solid digestion via drawing moisture out by forward osmosis (FO). Methane production and microbial community evolution were monitored in an ad-OMBR as the total solids (TS) content was gradually increased. With magnesium chloride (MgCl2) and cellulose triacetate (CTA) membrane as a draw solution and FO membrane, respectively, the ad-OMBR exhibited better performance than the conventional digester, with higher solid content, organic degradation and methane content in biogas. The conductivity of the ad-OMBR did not increase, potentially because of the formation of struvite crystals aided by the reverse-fluxed Mg2+ ions. Microbial diversity increased along with the increase in solid content based on the Shannon index, while the most operational taxonomic units were obtained in the 8% TS sludge Although phylum Firmicutes decreased when the TS content was raised to 11%, the relative abundance of Proteobacteria, Chloroflexi, Actinobacteria, and Bacteroidetes, which could also degrade organic matter, increased with increasing TS in ad-OMBR. FO membrane fouling in ad-OMBR was highly reversible.
Subject(s)
Membranes, Artificial , Sewage , Anaerobiosis , Bioreactors , Methane , OsmosisABSTRACT
Granular activated carbon (GAC) has been proved to accelerate the formation of aerobic granules during wastewater treatment. However, there has never been a study on the extracellular polymeric substances (EPS) or structural stability of the GAC aerobic granules. Thus, this study evaluated the impact of GAC on these characteristics. With GAC addition, granules matured 12 days earlier than those of the control group. Scanning electron microscopy showed the surface of aerobic granules enhanced by GAC to be denser and smoother than the surface of control granules, which could be the first line of defense against external selection pressure. After granules matured, there was no difference in contamination removal between the two types of granules. The protein content in EPS of GAC aerobic granules was higher than that of the control group; however, there was no difference in the polysaccharide content. EPS fluorescence in situ staining demonstrated that inside the aerobic granules, a high concentration of protein encapsulated the GAC. In addition, integrity coefficients indicated that GAC significantly improved the ability of aerobic granules to resist hydraulic shear. The result of hydrolase treatment proved that the outer layer structure of the GAC aerobic granules was maintained by ß-polysaccharide, and the inner layer structure was maintained by protein. The ability of GAC-enhanced aerobic granules to resist single hydrolase was stronger than that of the control group.
Subject(s)
Charcoal/chemistry , Extracellular Polymeric Substance Matrix/chemistry , Waste Disposal, Fluid , Aerobiosis , Bioreactors , Hydrolases/chemistry , Microscopy, Electron, Scanning , Polysaccharides/analysis , Polysaccharides/chemistry , Pressure , Proteins/analysis , Waste Disposal, Fluid/instrumentation , Waste Disposal, Fluid/methods , Wastewater/chemistryABSTRACT
This work elucidates the effects of model reversed salt MgCl2 on methane production in an anaerobic digestion bioreactor treating waste sludge. Along with MgCl2 concentration being raised stepwise, the methane production was only slightly less than in the control when MgCl2 was 20â¯g/L and under, and then suddenly reduced to only about 10â¯mL/(L·d) at a MgCl2 concentration of 30â¯g/L, and finally stopped when the MgCl2 concentration reached 50â¯g/L. However, the total relative abundance of methanogens Methanomicrobia and Methanobacteria still accounted for 84.97% of the archaeal community when MgCl2 was 50â¯g/L. The high correlation between live/dead cell ratio and methane production suggests that the live/dead cell ratio instead of the inhibition of methanogen might be the major cause for the halt of methane production at a magnesium chloride concentration of 50â¯g/L.
Subject(s)
Bioreactors , Magnesium Chloride/pharmacology , Sewage/microbiology , Anaerobiosis/drug effects , Methane , OsmosisABSTRACT
Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system, and its pathogenesis remains largely unclear. Much attention has been paid to the role of microRNAs (miRs) in regulation of autoimmune disease. Here, we found, for the first time, that miR-448 expression was significantly increased in periphery blood mononuclear cells (PBMC) and cerebrospinal fluid (CSF) of patients with MS, and its expression positively correlated with the disease severity. We further demonstrated that CD4+ T cells, especially the Th17 lineage, were the major source of miR-448 expression. Using gain- and loss-of-function approaches, we further verified that miR-448 could enhance Th17 differentiation, characterized by up-regulated expression levels of IL-17A and RORγt. Interleukin (IL)-1ß as a potent driver of pathogenic Th17 cells was able to strongly induce miR-448 expression in CD4+ T cells through activating NF-κB pathway. Additionally, we identified that miR-448 directly targeted protein tyrosine phosphatase non-receptor type 2 (PTPN2), which has been known as an anti-inflammatory player with capacity to suppress Th17 differentiation. We also observed markedly decreased expression of PTPN2 in PBMC and CSF of MS patients. Our results suggest that miR-448 might promote Th17 differentiation in MS and thus aggravate the disease through inhibiting PTPN2.
Subject(s)
Interleukin-17/genetics , MicroRNAs/genetics , Multiple Sclerosis/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 2/genetics , Th17 Cells/pathology , B-Lymphocytes/immunology , B-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Case-Control Studies , Cell Differentiation , Gene Expression Regulation , Genes, Reporter , Humans , Interleukin-17/immunology , Interleukin-1beta/genetics , Interleukin-1beta/immunology , Luciferases/genetics , Luciferases/metabolism , MicroRNAs/immunology , Multiple Sclerosis/diagnosis , Multiple Sclerosis/immunology , Multiple Sclerosis/pathology , NF-kappa B/genetics , NF-kappa B/immunology , Neutrophils/immunology , Neutrophils/pathology , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Nuclear Receptor Subfamily 1, Group F, Member 3/immunology , Primary Cell Culture , Protein Tyrosine Phosphatase, Non-Receptor Type 2/immunology , Remission Induction , Severity of Illness Index , Signal Transduction , Th17 Cells/immunologyABSTRACT
AIM: Free fatty acid-induced lipotoxicity plays a crucial role in the progression of nonalcoholic fatty liver disease (NAFLD). In the present study we investigated the effects of a high-fat diet and free fatty acids on the autophagic process in hepatocytes in vivo and in vitro and the underlying mechanisms. METHODS: LC3-II expression, a hallmark of autophagic flux, was detected in liver specimens from patients with non-alcoholic steatohepatitis (NASH) as well as in the livers of C57BL/6 mice fed a high-fat diet (HFD) up to 16 weeks. LC3-II expression was also analyzed in human SMMC-7721 and HepG2 hepatoma cells exposed to palmitic acid (PA), a saturated fatty acid. PA-induced apoptosis was detected by Annexin V staining and specific cleavage of PARP in the presence and absence of different agents. RESULTS: LC3-II expression was markedly increased in human NASH and in liver tissues of HFD-fed mice. Treatment of SMMC-7721 cells with PA increased LC3-II expression in time- and dose-dependent manners, whereas the unsaturated fatty acid oleic acid had no effect. Inhibition of autophagy with 3MA sensitized SMMC-7721 cells to PA-induced apoptosis, whereas activation of autophagy by rapamycin attenuated PA-induced PARP cleavage. The autophagy-associated proteins Beclin1 and Atg5 were essential for PA-induced autophagy in SMMC-7721 cells. Moreover, pretreatment with SP600125, an inhibitor of JNK, effectively abrogated PA-mediated autophagy and apoptosis. Specific knockdown of JNK2, but not JNK1, in SMMC-7721 cells significantly suppressed PA-induced autophagy and enhanced its pro-apoptotic activity; whereas specific knockdown of JNK1 had the converse effect. Similar results were obtained when HepG2 cells were tested. CONCLUSION: JNK1 promotes PA-induced lipoapoptosis, whereas JNK2 activates pro-survival autophagy and inhibits PA lipotoxicity. Our results suggest that modulation of autophagy may have therapeutic benefits in the treatment of lipid-related metabolic diseases.
Subject(s)
Autophagy/drug effects , Hepatocytes/drug effects , Mitogen-Activated Protein Kinase 9/metabolism , Non-alcoholic Fatty Liver Disease/enzymology , Palmitic Acid/toxicity , Animals , Apoptosis/drug effects , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/metabolism , Autophagy-Related Protein 5 , Beclin-1 , Diet, High-Fat , Disease Models, Animal , Dose-Response Relationship, Drug , Enzyme Activation , Hep G2 Cells , Hepatocytes/enzymology , Hepatocytes/pathology , Humans , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice, Inbred C57BL , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitogen-Activated Protein Kinase 8/genetics , Mitogen-Activated Protein Kinase 8/metabolism , Mitogen-Activated Protein Kinase 9/antagonists & inhibitors , Mitogen-Activated Protein Kinase 9/genetics , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/pathology , Protein Kinase Inhibitors/pharmacology , RNA Interference , Signal Transduction/drug effects , Time Factors , TransfectionABSTRACT
Hepatoblastoma (HB) is a rare cancer but represents the most common liver malignancy in children under 3 years of age. Nevertheless, a clear understanding of the pathogenesis is lacking. Although the treatment of HB has been dramatically improved by combining chemotherapy regimens with surgery, its fatal outcome of fast development and recurrence makes new treatment strategies for HB, based on an improved understanding of the pathogenesis, essential. Autophagy is believed to be important in the progression of cancers. However, the role of autophagy in HB remains to be elucidated. Here, we show that autophagy is activated in HB tissues and cells under the conditions of starvation or chemotherapy, coupled with the over-expression of autophagic-related genes BECN1 and ATG5. Suppression of autophagy with pharmacological agents and small interfering RNAs significantly increased cell apoptosis and retarded proliferation in response to nutrition deprivation and treatment with chemotherapeutics. Our data demonstrate that the BECN1 and ATG5-dependent phosphoinositide 3-kinase (PI3K) signaling pathway is essential for the survival of HB cells and their tolerance to chemotherapy and starvation-induced death, and suggests that modifying such autophagic genes may suppress the development of HB, thus offering a therapeutic potential for patients with HB.
Subject(s)
Apoptosis Regulatory Proteins/biosynthesis , Autophagy/drug effects , Hepatoblastoma/etiology , Liver Neoplasms/etiology , Membrane Proteins/biosynthesis , Microtubule-Associated Proteins/biosynthesis , Apoptosis/drug effects , Apoptosis Regulatory Proteins/physiology , Autophagy/physiology , Autophagy-Related Protein 5 , Beclin-1 , Cell Line, Tumor , Child, Preschool , Hepatoblastoma/drug therapy , Humans , Liver Neoplasms/drug therapy , Membrane Proteins/physiology , Microtubule-Associated Proteins/physiology , Phosphatidylinositol 3-Kinases/physiology , RNA, Small Interfering/pharmacology , Signal Transduction/physiologyABSTRACT
UNLABELLED: One of the challenges surrounding nonalcoholic fatty liver disease (NAFLD) is to discover the mechanisms that underlie the initiation of it. The aim of the present study was to elucidate the effects of Toll-like receptor 4 (TLR4) signaling in liver parenchymal cells during the early stage of NAFLD. Male TLR4-wildtype, TLR4-knockout, TLR2-knockout, MyD88-knockout, and TRIF-knockout mice were fed a normal diet or high-fat diet (HFD). Liver steatosis, alanine aminotransferase levels, nuclear translocation of nuclear factor kappa B (NF-κB) (p65), macrophage accumulation, and neutrophil infiltration were assessed. Using Kupffer cell depletion or bone marrow transplantation, we examined the potential role of Kupffer cells and myeloid infiltrating cells during the initiation of NAFLD. Immunohistochemistry and western blotting were implemented to determine the release of high-mobility group box1 (HMGB1). The neutral-antibody against HMGB1 was used to block the activity of free HMGB1. Here we report that the activation of TLR4 signaling in hepatocytes, accompanied with the relocation of P65 in nucleus, was proven to play an important role during the initiation of NAFLD. Importantly, HMGB1 releasing from hepatocytes in response to free fatty acid (FFA) infusion was first reported as the key molecule for the TLR4/MyD88 activation and cytokines expression in vitro and in vivo. Treatment with neutralizing antibody to HMGB1 protects against FFA-induced tumor necrosis factor alpha and interleukin-6 production. CONCLUSION: Our study supports the notion that TLR4/MyD88 signaling in liver parenchymal cells plays a pivotal role during the early progression of HFD-induced NAFLD, in which free HMGB1 served as a positive component mediating TLR4 activation.
Subject(s)
Fatty Liver/metabolism , HMGB1 Protein/metabolism , Hepatocytes/metabolism , Signal Transduction/physiology , Toll-Like Receptor 4/metabolism , Animals , Cytokines/metabolism , Fatty Liver/pathology , Fatty Liver/physiopathology , HMGB1 Protein/genetics , Hepatocytes/pathology , Kupffer Cells/metabolism , Kupffer Cells/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout , Myeloid Cells/metabolism , Myeloid Cells/pathology , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , NF-kappa B/metabolism , Non-alcoholic Fatty Liver Disease , Toll-Like Receptor 4/geneticsABSTRACT
BACKGROUND: Oxidative stress has been implicated in the pathogenesis of a wide spectrum of human diseases, including Hepatitis B virus (HBV)-related liver disease. Hepatitis B virus X protein (HBx) is a key regulator of HBV that exerts pleiotropic activity on cellular functions. Recent studies showed that HBx alters mitochondrial membrane potential, thereby sensitizing cells to pro-apoptotic signals. However, it remains largely unknown whether susceptibility of hepatocytes could be disturbed by HBx under oxidative stress conditions. The purpose of this study is to determine the apoptotic susceptibility of HBx-expressing hepatocytes upon exposure to pro-oxidant stimuli in vitro and in vivo and explore its underlying mechanism. RESULTS: Although expression of HBx itself did not activate apoptotic signaling, it significantly enhanced oxidative stress-induced cell death both in vitro and in vivo. Interestingly, this phenomenon was associated with a pronounced reduction of protein levels of Mcl-1, but not other anti-apoptotic Bcl-2 members. Importantly, enforced expression of Mcl-1 prevented HBx-triggered cell apoptosis; conversely, specific knockdown of Mcl-1 exacerbated HBx-induced apoptosis upon exposure to oxidative stress. Furthermore, inhibition of caspase-3 not only abrogated HBx-triggered apoptotic killing but also blocked HBx-induced Mcl-1 loss. Additionally, expression of HBx and Mcl-1 was found to be inversely correlated in HBV-related hepatocellular carcinogenesis (HCC) tissues. CONCLUSIONS: Our findings indicate that HBx exerts pro-apoptotic effect upon exposure to oxidative stress probably through accelerating the loss of Mcl-1 protein via caspase-3 cascade, which may shed a new light on the molecular mechanism of HBV-related hepatocarcinogenesis.
Subject(s)
Apoptosis/physiology , Caspase 3/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Trans-Activators/metabolism , Analysis of Variance , Animals , HEK293 Cells , Hep G2 Cells , Humans , Liver/blood supply , Mice , Mice, Transgenic , Myeloid Cell Leukemia Sequence 1 Protein , Oxidative Stress/physiology , Trans-Activators/biosynthesis , Trans-Activators/genetics , Transfection , Viral Regulatory and Accessory Proteins , Warm IschemiaABSTRACT
AIM: To study the prognostic factors for intrahepatic cholangiocarcinoma (ICC) and evaluate the impact of chronic hepatitis B virus (HBV) infection on survival rate of ICC patients. METHODS: A total of 155 ICC patients who underwent macroscopic curative resections (R0 and R1) were enrolled in this retrospective study and divided into group A with HBV infection and group B without HBV infection according to their chronic HBV infection, represented by positive hepatitis B surface antigen (HBsAg) in serum or in liver tissue. Clinicopathological characteristics and survival rate of the patients were evaluated. RESULTS: All patients underwent anatomical resection. Their 1- and 3-year survival rates were 60.6% and 32.1%, respectively. Multivariate analyses revealed that HBV infection, hepatolithiasis, microscopic satellite lesion, and lymphatic metastasis were the independent prognostic factors for the survival rate of ICC patients. The median disease-free survival time of the patients was 5.0 mo. The number of tumors, microscopic satellite lesion, and vascular invasion were the independent prognostic factors for the disease-free survival rate of the patients. The prognostic factors affecting the survival rate of ICC patients with HBV infection and those without HBV infection were not completely consistent. Alkaline phosphatase > 119 U/L, microscopic satellite lesion, vascular invasion, and lymphatic metastasis were the independent factors for the patients with HBV infection, while r-glutamyltransferase > 64 U/L, microscopic satellite lesion, and poor tumor differentiation were the independent factors for the patients without HBV infection. CONCLUSION: HBV infection is a valuable clinical factor for predicting tumor invasiveness and clinical outcome of ICC patients. ICC patients with HBV infection should be distinguished from those without HBV infection because they have different clinicopathological characteristics, prognostic factors and outcomes after surgical resection.
Subject(s)
Hepatitis B Surface Antigens/metabolism , Hepatitis B/diagnosis , Hepatitis B/virology , Adult , Aged , Bile Duct Neoplasms/diagnosis , Bile Duct Neoplasms/surgery , Bile Duct Neoplasms/virology , Bile Ducts, Intrahepatic , Cholangiocarcinoma/diagnosis , Cholangiocarcinoma/surgery , Cholangiocarcinoma/virology , Female , Hepatitis B virus/metabolism , Humans , Liver/virology , Liver Neoplasms/diagnosis , Liver Neoplasms/surgery , Liver Neoplasms/virology , Male , Middle Aged , Multivariate Analysis , Neoplasm Invasiveness , Prognosis , Retrospective Studies , Treatment OutcomeABSTRACT
Hepatitis B virus X protein (HBx) is implicated in the pathogenesis of hepatitis B virus (HBV)-associated liver diseases. However, whether HBx has the ability to disturb the susceptibility of hepatocytes to common chemotherapeutic agents remains incompletely understood. Here we demonstrate that HBx enhances cisplatin-induced hepatotoxicity by a mechanism involving degradation of Mcl-1, an antiapoptotic member of the Bcl-2 family. Ectopic expression of HBx sensitized hepatocytes to cisplatin-induced apoptosis, which was accompanied by a marked downregulation of Mcl-1 but not of Bcl-2 or Bcl-xL. Overexpression of Mcl-1 prevented HBx-induced proapoptotic and proinflammatory effects during cisplatin treatment both in vitro and in vivo. HBx-induced dysregulation of Mcl-1 resulted mainly from posttranslational degradation rather than transcription repression. Moreover, a caspase-3 inhibitor effectively abrogated HBx-enhanced Mcl-1 degradation and cell death. Importantly, antioxidants blocked activation of caspase-3 and acceleration of Mcl-1 loss, as well as cell death, in HBx-expressing hepatocytes upon cisplatin exposure in vitro and in vivo. Collectively, these data implicate oxidative stress-dependent caspase-3-mediated degradation of Mcl-1 as a mechanism contributing to HBx-mediated sensitization of cisplatin-induced hepatotoxicity. A combination of cisplatin and antioxidants might provide more advantage than cisplatin alone in the treatment of cancer patients with chronic HBV infection.
Subject(s)
Cisplatin/toxicity , Hepatitis B virus/pathogenicity , Hepatocytes/pathology , Hepatocytes/virology , Proto-Oncogene Proteins c-bcl-2/metabolism , Trans-Activators/metabolism , Virulence Factors/metabolism , Animals , Apoptosis , Caspase 3/metabolism , Cells, Cultured , Humans , Liver/pathology , Liver/virology , Mice , Mice, Nude , Myeloid Cell Leukemia Sequence 1 Protein , Oxidative Stress , Rats , Viral Regulatory and Accessory ProteinsABSTRACT
BACKGROUND & AIMS: Reactive oxygen species (ROS) are considered to play a prominent causative role in the development of various hepatic disorders. Antioxidants have been effectively demonstrated to protect against hepatic damage. Hydrogen (H(2)), a new antioxidant, was reported to selectively reduce the strongest oxidants, such as hydroxyl radicals (·OH) and peroxynitrite (ONOO(-)), without disturbing metabolic oxidation-reduction reactions or disrupting ROS involved in cell signaling. In place of H(2) gas, hydrogen-rich saline (HS) may be more suitable for clinical application. We herein aim to verify its protective effects in experimental models of liver injury. METHODS: H(2) concentration in vivo was detected by hydrogen microelectrode for the first time. Liver damage, ROS accumulation, cytokine levels, and apoptotic protein expression were, respectively, evaluated after GalN/LPS, CCl(4), and DEN challenge. Simultaneously, CCl(4)-induced hepatic cirrhosis and DEN-induced hepatocyte proliferation were measured. RESULTS: HS significantly increased hydrogen concentration in liver and kidney tissues. As a result, acute liver injury, hepatic cirrhosis, and hepatocyte proliferation were reduced through the quenching of detrimental ROS. Activity of pro-apoptotic players, such as JNK and caspase-3, were also inhibited. CONCLUSIONS: HS could protect against liver injury and also inhibit the processes leading to liver cirrhosis and hepatocyte compensatory proliferation.
Subject(s)
Antioxidants/administration & dosage , Chemical and Drug Induced Liver Injury/prevention & control , Hydrogen/administration & dosage , Sodium Chloride/administration & dosage , Animals , Antioxidants/metabolism , Apoptosis/drug effects , Cell Proliferation/drug effects , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Disease Models, Animal , Hydrogen/metabolism , Injections, Intraperitoneal , JNK Mitogen-Activated Protein Kinases/metabolism , Kidney/drug effects , Kidney/metabolism , Liver/drug effects , Liver/metabolism , Liver/pathology , Liver Cirrhosis, Experimental/prevention & control , Liver Failure, Acute/metabolism , Liver Failure, Acute/pathology , Liver Failure, Acute/prevention & control , Male , Mice , Mice, Inbred C57BL , Reactive Oxygen Species/metabolism , Signal Transduction/drug effectsABSTRACT
ß-catenin is a key molecule involved in both cell-cell adhesion and Wnt signaling pathway. In our study, we found that, in the development of hepatocellular carcinoma (HCC), ß-catenin was correlated with hepatitis B virus (HBV) X gene encoded protein, which is essential for HBV infectivity and is a potential cofactor in viral carcinogenesis. The expression levels of wild-type ß-catenin and E-cadherin were decreased in HepG2 cells expressing hepatitis B virus X protein (HBx), accompanied by destabilization of adherens junction. Reverse transcriptase PCR (RT-PCR), Northern and Western blot showed that reduction of wild-type ß-catenin expression involved degradation of the protein. However, RNA interference (RNAi) and luciferase assay indicated that HBx enhanced ß-catenin mediated signaling in HepG2 cells. In addition, immunohistochemical and Western blot analysis of ß-catenin revealed that a decrease in the ß-catenin protein level was found in 58.3% of HBV-related HCCs versus 19.2% of non-HBV-related tumors. Our data suggest that the expression of HBx contributed to the development of HCC, in part, by repressing the wild-type ß-catenin expression and enforcing ß-catenin-dependent signaling pathway, thus inducing cellular changes leading to acquisition of metastatic and/or proliferation properties.