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1.
Can J Infect Dis Med Microbiol ; 2023: 5602401, 2023.
Article in English | MEDLINE | ID: mdl-37680457

ABSTRACT

Both schizophrenia (SZ) and multiple sclerosis (MS) affect millions of people worldwide and impose a great burden on society. Recent studies indicated that MS elevated the risk of SZ and vice versa, whereas the underlying pathological mechanisms are still obscure. Considering that fecal microbiota played a vital role in regulating brain functions, the fecal microbiota and serum cytokines from 90 SZ patients and 71 age-, gender-, and BMI-matched cognitively normal subjects (referred as SZC), 22 MS patients and 33 age-, gender-, and BMI-matched healthy subjects (referred as MSC) were analyzed. We found that both diseases demonstrated similar microbial diversity and shared three differential genera, including the down-regulated Faecalibacterium, Roseburia, and the up-regulated Streptococcus. Functional analysis indicated that the three genera were involved in pathways such as "carbohydrate metabolism" and "amino acid metabolism." Moreover, the variation patterns of serum cytokines associated with MS and SZ patients were a bit different. Among the six cytokines perturbed in both diseases, TNF-α increased, while IL-8 and MIP-1α decreased in both diseases. IL-1ra, PDGF-bb, and RANTES were downregulated in MS patients but upregulated in SZ patients. Association analyses showed that Faecalibacterium demonstrated extensive correlations with cytokines in both diseases. Most notably, Faecalibacterium correlated negatively with TNF-α. In other words, fecal microbiota such as Faecalibacterium may contribute to the coexistence of MS and SZ by regulating serum cytokines. Our study revealed the potential roles of fecal microbiota in linking MS and SZ, which paves the way for developing gut microbiota-targeted therapies that can manage two diseases with a single treat.

2.
BMC Plant Biol ; 22(1): 179, 2022 Apr 07.
Article in English | MEDLINE | ID: mdl-35392808

ABSTRACT

BACKGROUND: To illustrate the molecular mechanism of mycoheterotrophic interactions between orchids and fungi, we assembled chromosome-level reference genome of Gastrodia menghaiensis (Orchidaceae) and analyzed the genomes of two species of Gastrodia. RESULTS: Our analyses indicated that the genomes of Gastrodia are globally diminished in comparison to autotrophic orchids, even compared to Cuscuta (a plant parasite). Genes involved in arbuscular mycorrhizae colonization were found in genomes of Gastrodia, and many of the genes involved biological interaction between Gatrodia and symbiotic microbionts are more numerous than in photosynthetic orchids. The highly expressed genes for fatty acid and ammonium root transporters suggest that fungi receive material from orchids, although most raw materials flow from the fungi. Many nuclear genes (e.g. biosynthesis of aromatic amino acid L-tryptophan) supporting plastid functions are expanded compared to photosynthetic orchids, an indication of the importance of plastids even in totally mycoheterotrophic species. CONCLUSION: Gastrodia menghaiensis has the smallest proteome thus far among angiosperms. Many of the genes involved biological interaction between Gatrodia and symbiotic microbionts are more numerous than in photosynthetic orchids.


Subject(s)
Gastrodia , Mycorrhizae , Orchidaceae , Gastrodia/genetics , Mycorrhizae/genetics , Orchidaceae/genetics , Orchidaceae/microbiology , Phylogeny , Symbiosis/genetics
3.
Rev Esp Enferm Dig ; 111(2): 101-105, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30318894

ABSTRACT

AIM: the number of intestinal IgA+ lymphocytes are decreased in acute liver necrosis and the mechanism remains poorly understood. The purpose of this study was to observe the role of lymphocyte homing and apoptosis associated with decreased intestinal IgA positive lymphocytes in acute liver necrosis. METHODS: the acute liver necrosis mouse model and LTßR pre-treatment were used to assess intestinal mucosal addressin cell adhesion molecule-1 (MAdCAM - 1) expression, cell apoptosis, IgA+ cells and secretory immunoglobulin A (SIgA). RESULTS: MAdCAM - 1 mRNA and protein expression decreased significantly in the acute necrosis group; 0.57 ± 0.032 fold vs. baseline (p < 0.05) and 0.45 ± 0.072 fold vs. baseline (p < 0.05), respectively. LTßR pre-treatment could significantly improve the decline of MAdCAM - 1 mRNA and protein expression in the intestinal mucosa (1.83 ± 0.064 fold vs. baseline, p < 0.05 and 1.75 ± 0.046 fold vs. baseline, p < 0.05, respectively) and partially restore the decline in IgA+ lymphocytes and SIgA levels. There were increased rates of enterocyte apoptosis in both the acute liver necrosis and LTßR pre-treatment group; 0.79% vs. control (p < 0.05) and 0.77% vs. control (p < 0.05), respectively). CONCLUSION: our results suggest that the dysfunction of lymphocyte homing and apoptosis are both involved with decreased intestinal IgA+ lymphocytes in acute liver necrosis. LTßR pre-treatment can partially restore IgA+ cells and SIgA by increasing MAdCAM - 1 expression, rather than inhibiting lymphocyte apoptosis.


Subject(s)
Cell Adhesion Molecules/analysis , Cell Movement/physiology , Immunoglobulin A/analysis , Liver/pathology , Lymphocytes/physiology , Mucoproteins/analysis , Alanine Transaminase/blood , Animals , Apoptosis , Aspartate Aminotransferases/blood , Cell Adhesion Molecules/genetics , Cell Movement/immunology , Disease Models, Animal , Enterocytes/physiology , Immunity, Mucosal/immunology , Immunoglobulin A, Secretory/analysis , In Situ Nick-End Labeling , Liver/immunology , Lymphocytes/immunology , Male , Mice , Mice, Inbred BALB C , Mucoproteins/genetics , Necrosis/immunology , Necrosis/pathology , RNA, Messenger/analysis
4.
Chin Med J (Engl) ; 136(12): 1390-1400, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37200041

ABSTRACT

ABSTRACT: The intestinal mucus layer is a barrier that separates intestinal contents and epithelial cells, as well as acts as the "mucus layer-soil" for intestinal flora adhesion and colonization. Its structural and functional integrity is crucial to human health. Intestinal mucus is regulated by factors such as diet, living habits, hormones, neurotransmitters, cytokines, and intestinal flora. The mucus layer's thickness, viscosity, porosity, growth rate, and glycosylation status affect the structure of the gut flora colonized on it. The interaction between "mucus layer-soil" and "gut bacteria-seed" is an important factor leading to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Probiotics, prebiotics, fecal microbiota transplantation (FMT), and wash microbial transplantation are efficient methods for managing NAFLD, but their long-term efficacy is poor. FMT is focused on achieving the goal of treating diseases by enhancing the "gut bacteria-seed". However, a lack of effective repair and management of the "mucus layer-soil" may be a reason why "seeds" cannot be well colonized and grow in the host gut, as the thinning and destruction of the "mucus layer-soil" is an early symptom of NAFLD. This review summarizes the existing correlation between intestinal mucus and gut microbiota, as well as the pathogenesis of NAFLD, and proposes a new perspective that "mucus layer-soil" restoration combined with "gut bacteria-seed" FMT may be one of the most effective future strategies for enhancing the long-term efficacy of NAFLD treatment.


Subject(s)
Gastrointestinal Microbiome , Non-alcoholic Fatty Liver Disease , Probiotics , Humans , Non-alcoholic Fatty Liver Disease/therapy , Prebiotics , Fecal Microbiota Transplantation , Bacteria , Liver/pathology
5.
Eng Comput ; : 1-32, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37362240

ABSTRACT

Understanding the microstructure-property relationships of porous media is of great practical significance, based on which macroscopic physical properties can be directly derived from measurable microstructural informatics. However, establishing reliable microstructure-property mappings in an explicit manner is difficult, due to the intricacy, stochasticity, and heterogeneity of porous microstructures. In this paper, a data-driven computational framework is presented to investigate the inherent microstructure-permeability linkage for natural porous rocks, where multiple techniques are integrated together, including microscopy imaging, stochastic reconstruction, microstructural characterization, pore-scale simulation, feature selection, and data-driven modeling. A large number of 3D digital rocks with a wide porosity range are acquired from microscopy imaging and stochastic reconstruction techniques. A broad variety of morphological descriptors are used to quantitatively characterize pore microstructures from different perspectives, and they compose the raw feature pool for feature selection. High-fidelity lattice Boltzmann simulations are conducted to resolve fluid flow passing through porous media, from which reliable permeability references are obtained. The optimal feature set that best represents permeability is identified through a performance-oriented feature selection process, upon which a cost-effective surrogate model is rapidly fitted to approximate the microstructure-permeability mapping via data-driven modeling. This surrogate model exhibits great advantages over empirical/analytical formulas in terms of prediction accuracy and generalization capacity, which can predict reliable permeability values spanning four orders of magnitude. Besides, feature selection also greatly enhances the interpretability of the data-driven prediction model, from which new insights into the mechanism of how microstructural characteristics determine intrinsic permeability are obtained.

6.
Clin Chim Acta ; 538: 203-210, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36549641

ABSTRACT

BACKGROUND AND AIMS: Metabolic dysfunction-associated fatty liver disease (MAFLD) brings heavy clinical and economic burdens to society, while understandings on heterogeneities are limited. MATERIALS AND METHODS: We conducted a serum metabolomics study to reveal the metabolic heterogeneities and develop a diagnostic strategy for MAFLD using a discovery set consisting of 122 biopsy-proven MAFLD patients [lean (n = 12), overweight (n = 20), obese (n = 74), type 2 diabetes mellitus (T2DM, n = 16)] and 35 controls, and a validation set containing 60 biopsy-proven MAFLD patients (20 lean, 20 obese and 20 T2DM) and 20 controls. RESULTS: Mitochondrial dysfunction, destructed phospholipids homeostasis, and folate deficiency were most severe in MAFLD concurrent T2DM patients. Formiminoglutamate, sphinganine and sphingosine correlated positively with HbA1c, while glycoursodeoxycholicacidsulfate correlated positively with AST. Additionally, the linear discriminant analysis (LDA) model using metabolites 5-hydroxyhexanoate, ribitol and formiminoglutamate demonstrated pretty good performance in screening for MAFLD patients, with AUC for validation samples being 0.94 (CI: 0.88-1.0). For easier clinical applications, an M-index based on the three metabolites was further designed. CONCLUSION: Our study supports that MAFLD concurrent T2DM patients deserve particular attentions in clinical follow-up, and paves the way for developing more effective diagnostic options in future studies.


Subject(s)
Diabetes Mellitus, Type 2 , Non-alcoholic Fatty Liver Disease , Humans , Diabetes Mellitus, Type 2/diagnosis , Metabolomics , Discriminant Analysis , Histidine , Non-alcoholic Fatty Liver Disease/diagnosis , Obesity
7.
Biomed Res Int ; 2022: 3742447, 2022.
Article in English | MEDLINE | ID: mdl-35757472

ABSTRACT

Glioma is one of the most common intracranial malignancies that plagues people around the world. Despite current improvements in treatment, the prognosis of glioma is often unsatisfactory. Necroptosis is a form of programmed cell death. As research progresses, the role of necroptosis in tumors has gradually attracted the attention of researchers. And lncRNA is regarded as a critical role in the development of cancer. Therefore, this study is aimed at establishing a prognostic model based on necroptosis-associated lncRNAs to accurately assess the prognosis and immune response of patients with glioma. The RNA sequences of glioma patients and normal brain samples were downloaded from The Cancer Genome Atlas (TCGA) and GTEx databases, respectively. The coexpression analysis was performed to identify the necroptosis-related lncRNAs. Then, we utilized LASSO analysis following univariate Cox analysis to construct a prognostic model. Subsequently, we applied the Kaplan-Meier curve, time-dependent receiver operating characteristics (ROC), and univariate and multivariate Cox regression analyses to assess the effectiveness of this model. And the functional enrichment analyses and immune-related analyses were employed to investigate the potential biological functions. A validation set was obtained from the Chinese Glioma Genome Atlas (CGGA) database. And qRT-PCR was employed to further validate the expression levels of selected necroptosis-associated lncRNAs. Seven necroptosis-related lncRNAs (FAM13A-AS1, JMJD1C-AS1, LBX2-AS1, ZBTB20-AS4, HAR1A, SNHG14, and LINC00900) were determined to construct a prognostic model. The area under the ROC curve (AUC) was 0.871, 0.901, and 0.911 at 1, 2, and 3 years, respectively. The risk score was shown to be an important independent predictor in both univariate and multivariate Cox regression analyses. Through functional enrichment analyses, we found that the differentially expressed genes (DEGs) were mainly enriched in protein binding and signaling-related biological functions and immune-associated pathways. In conclusion, we established and validated a novel necroptosis-related lncRNA signature, which could accurately predict the overall survival of glioma patients and serve as potential therapeutic targets.


Subject(s)
Glioma , RNA, Long Noncoding , Biomarkers, Tumor/genetics , GTPase-Activating Proteins/genetics , Gene Expression Regulation, Neoplastic , Glioma/genetics , Humans , Immunity , Jumonji Domain-Containing Histone Demethylases/genetics , Kaplan-Meier Estimate , Necroptosis/genetics , Oxidoreductases, N-Demethylating/genetics , Oxidoreductases, N-Demethylating/metabolism , Prognosis , RNA, Long Noncoding/metabolism
8.
Nephrol Dial Transplant ; 26(1): 75-83, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20615908

ABSTRACT

BACKGROUND: Little information is available regarding the mechanisms involved in cytokine-induced type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R1) expression in human mesangial cells (HMCs) in the occurrence of hepatorenal syndrome (HRS). Over-expression of IP(3)R1 would enhance both IP(3)-binding activity and sensitivity. We hypothesize that it is possible that increased IP(3)R1, induced by TNFα, would lead to increased IP(3) sensitivity in response to a variety of vasoconstrictors, and promote HMC contraction and thus lead to reduced GFP, promoting HRS occurrence and development. METHODS: Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effects of TNFα on IP(3)R1 mRNA and protein expression. Several inhibitors of kinases, depletion PKC, over-expression of dominant-negative mutant of PKC and non-radioactive PKC assay were used to examine the mechanism of signal transduction of TNFα-regulated IP(3)R1 in HMCs. RESULTS: TNFα increased IP(3)R1 mRNA and protein expression in HMCs, an effect that was blocked by prolonged incubated chronic PMA, D609, safingol and also by transfection with domain-negative PKCα construct. TNFα activated and promoted autophosphorylation of the PKCα. In addition, both anti-TNFR1 and anti-TNFR2 antibodies blocked TNFα-induced IP(3)R1 protein expression, while only anti-TNFR1 antibodies but not anti-TNFR2 antibodies attenuated TNFα-induced PKCα activity. CONCLUSIONS: TNFα increased the expression of IP(3)R1, and this was mediated, at least in part, through the TNFR1/PC-PLC/PKCα and TNFR2 signalling pathways in HMCs.


Subject(s)
Inositol 1,4,5-Trisphosphate Receptors/metabolism , Mesangial Cells/drug effects , Protein Kinase C-alpha/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Type C Phospholipases/metabolism , Blotting, Western , Calcium/metabolism , Cells, Cultured , Hepatorenal Syndrome/metabolism , Hepatorenal Syndrome/pathology , Humans , Inositol 1,4,5-Trisphosphate/metabolism , Inositol 1,4,5-Trisphosphate Receptors/genetics , Mesangial Cells/metabolism , Protein Kinase C-alpha/genetics , RNA, Messenger/genetics , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type II/genetics , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction
9.
Cell Oncol (Dordr) ; 43(3): 461-475, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32207044

ABSTRACT

PURPOSE: The iron-chelating agent di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT) has been found to inhibit cell growth and to induce apoptosis in several human cancers. However, its effects and mechanism of action in glioma are unknown. METHODS: Human glioma cell line LN229 and patient-derived glioma stem cells GSC-42 were applied for both in vitro and in vivo xenograft nude mouse experiments. The anti-tumor effects of Dp44mT were assessed using MTS, EdU, TUNEL, Western blotting, qRT-PCR, luciferase reporter, chromatin immunoprecipitation and immunohistochemical assays. RESULTS: We found that Dp44mT can upregulate the expression of the anti-oncogene N-myc downstream-regulated gene (NDRG)2 by directly binding to and activating the RAR-related orphan receptor (ROR)A. In addition, we found that NDRG2 overexpression suppressed inflammation via activation of interleukin (IL)-6/Janus kinase (JAK)2/signal transducer and activator of transcription (STAT)3 signaling. CONCLUSIONS: Our data indicate that Dp44mT may serve as an effective drug for the treatment of glioma by targeting RORA and enhancing NDRG2-mediated IL-6/JAK2/STAT3 signaling.


Subject(s)
Apoptosis/drug effects , Glioma/pathology , Iron Chelating Agents/pharmacology , Janus Kinase 2/metabolism , Nuclear Receptor Subfamily 1, Group F, Member 1/metabolism , STAT3 Transcription Factor/metabolism , Thiosemicarbazones/pharmacology , Tumor Suppressor Proteins/metabolism , Animals , Carcinogenesis/drug effects , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , Interleukin-6/metabolism , Mice, Inbred BALB C , Models, Biological , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Signal Transduction/drug effects , Transcription, Genetic/drug effects , Tumor Suppressor Proteins/genetics
10.
J Org Chem ; 74(4): 1770-3, 2009 Feb 20.
Article in English | MEDLINE | ID: mdl-19133786

ABSTRACT

Rate constants for thermal cis-to-trans isomerization of N-(phenylazo)-substituted nitrogen ring heterocyles were determined as a function of phenyl ring substitution, cyclic amine ring size, and organic solvents. Observed first-order rate constants are found to increase with increasing electron-withdrawing character of the para substituent, with larger amine rings, and with increasing solvent polarity. Overall, trends observed are consistent with geometrical isomerization taking place through rotation around the nitrogen-nitrogen double bond via a polarized transition state.

11.
Chem Commun (Camb) ; 51(13): 2645-8, 2015 Feb 14.
Article in English | MEDLINE | ID: mdl-25572688

ABSTRACT

A MOF-253 supported active Ru carbonyl complex (MOF-253-Ru(CO)2Cl2) was constructed for photocatalytic CO2 reduction under visible light irradiation. Its performance can be further improved by immobilization as a photosensitizer. This study highlights the great potential of using MOFs as a solid ligand and platform for the assembly of a complicated catalytic system.

12.
ACS Appl Mater Interfaces ; 6(5): 3483-90, 2014 Mar 12.
Article in English | MEDLINE | ID: mdl-24548075

ABSTRACT

Highly reductive RGO (reduced graphene oxide)/ZnIn2S4 nanocomposites with a sheet-on-sheet morphology have been prepared via a facile one-pot solvothermal method in a mixture of N,N-dimethylformamide (DMF) and ethylene glycol (EG) as solvent. A reduction of GO (graphene oxide) to RGO and the formation of ZnIn2S4 nanosheets on highly reductive RGO has been simultaneously achieved. The effect of the solvents on the morphology of final products has been investigated and the formation mechanism was proposed. The as-prepared RGO/ZnIn2S4 nanoscomposites were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), N2-adsorption BET surface area, UV-vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM). The photocatalytic activity for hydrogen evolution under visible light irradiations over the as-prepared RGO/ZnIn2S4 nanocomposites has been investigated. The as-prepared RGO/ZnIn2S4 nanocomposites show enhanced photocatalytic activity for hydrogen evolution under visible light irradiations and an optimum photocatalytic activity is observed over 1.0 wt % RGO incorporated ZnIn2S4 nanocomposite. The superior photocatalytic performance observed over RGO/ZnIn2S4 nanocomposites can be ascribed to the existence of highly reductive RGO which has strong interactions with ZnIn2S4 nanosheets. The existence of the strong interaction between ZnIn2S4 nanosheets and RGO in the nancomposites facilitates the electron transfer from ZnIn2S4 to RGO, with the latter serving as a good electron acceptor, mediator as well as the co-catalyst for hydrogen evolution. This study can provide some guidance for us in the developing of RGO-incorporated nanocomposite photocatalysts.

14.
World J Gastroenterol ; 18(36): 5042-50, 2012 Sep 28.
Article in English | MEDLINE | ID: mdl-23049212

ABSTRACT

AIM: To determine the effect of tumor necrosis factor alpha (TNF-α) on intestinal permeability (IP) in mice with fulminant hepatic failure (FHF), and the expression of tight junction proteins. METHODS: We selected D-lactate as an index of IP, induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α, assessed the results using an enzymatic-spectrophotometric method, transmission electron microscopy, immunohistochemistry, Western blotting and real-time quantitative polymerase chain reaction. The effect of the administration of anti-TNF-α immunoglobulin G (IgG) antibody, before the administration of D-galactosamine/lipopolysaccharide, on TNF-α was also assessed. RESULTS: IP was significantly increased in the mouse model of FHF 6 h after injection (13.57 ± 1.70 mg/L, 13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L, P = 0.001). Electron microscopic analysis revealed tight junction (TJ) disruptions, epithelial cell swelling, and atrophy of intestinal villi. Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models (occludin: 0.57 ± 0.159 fold vs baseline, P = 0.000; claudin-1: 0.3067 ± 0.1291 fold vs baseline, P = 0.003), as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein (occludin: 0.61 ± 0.0473 fold vs baseline, P = 0.000; claudin-1: 0.6633 ± 0.0328 fold vs baseline, P = 0.000). Prophylactic treatment with anti-TNF-α IgG antibody prevented changes in IP (4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L, P = 0.791), intestinal tissue ultrastructure, and the mRNA levels of occludin and claudin-1 expression (occludin: 0.8865 ± 0.0274 fold vs baseline, P = 0.505; claudin-1: 0.85 ± 0.1437 fold vs baseline, P = 0.1), and in the protein levels (occludin: 0.9467 ± 0.0285 fold vs baseline, P > 0.05; claudin-1: 0.9533 ± 0.0186 fold vs baseline, P = 0.148). CONCLUSION: Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1, and destruction of the TJ in the colon, which were induced by TNF-α in FHF mice.


Subject(s)
Intestinal Mucosa/metabolism , Liver Failure, Acute/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Animals , Claudin-1/analysis , Claudin-1/genetics , Colon/ultrastructure , Intestinal Mucosa/ultrastructure , Lactic Acid/analysis , Male , Mice , Mice, Inbred BALB C , Occludin/analysis , Occludin/genetics , Permeability , RNA, Messenger/analysis , Tight Junctions/metabolism
15.
Eur J Gastroenterol Hepatol ; 23(7): 552-8, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21593677

ABSTRACT

OBJECTIVES: Cerebral edema is a major cause of death during acute liver failure (ALF), but the exact mechanism of this condition is still not entirely clear. The aim of this study was to investigate the role of tumor necrosis factor α (TNFα) in changing the permeability of the blood-brain barrier (BBB) during acetaminophen (APAP)-induced ALF. MATERIALS AND METHODS: ALF animal models were generated by administering APAP. Anti-TNFα-IgG was intravenously injected (100 µg/mouse) 2 h after administration of APAP. We investigated BBB permeability with Evans blue staining, and structure with electron microscopy. RESULTS: BBB permeability increased in APAP-induced ALF mice and correlated with elevated serum TNFα levels. Electron microscopy of mouse brain tissues revealed tight junction (TJ) disruptions and endothelial cell shrinkage, as well as increased vesicles and vacuoles. In addition, the expression of the TJ-associated protein, occludin, was significantly decreased in APAP-induced ALF mice. Changes in BBB permeability and occludin expression could be prevented by administering anti-TNFα-IgG 2 h after APAP challenge. CONCLUSION: TNFα plays a critical role in the development of brain edema in APAP-induced ALF. Increased BBB permeability may be due to the loss of the TJ-associated protein occludin.


Subject(s)
Acetaminophen/adverse effects , Analgesics, Non-Narcotic/adverse effects , Blood-Brain Barrier/physiopathology , Capillary Permeability , Liver Failure, Acute/chemically induced , Tumor Necrosis Factor-alpha/physiology , Animals , Antibodies, Neutralizing/therapeutic use , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/pathology , Blood-Brain Barrier/ultrastructure , Brain Edema/chemically induced , Brain Edema/pathology , Liver Failure, Acute/pathology , Male , Membrane Proteins/biosynthesis , Mice , Mice, Inbred BALB C , Occludin , Tight Junctions/drug effects , Tight Junctions/pathology , Tight Junctions/ultrastructure , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/immunology
16.
World J Gastroenterol ; 16(30): 3827-33, 2010 Aug 14.
Article in English | MEDLINE | ID: mdl-20698046

ABSTRACT

AIM: To investigate the number of intestinal immunoglobulin A (IgA+) plasma cells and expression of intestinal IgA in mice with acute liver necrosis. METHODS: A model of acute liver necrosis was established by intraperitoneal injection of galactosamine (GalN) and lipopolysaccharide (LPS). Sixty mice were randomly divided into one of 4 equal groups: normal control, acute liver necrosis, LPS, or GalN. Hematoxylin and eosin staining, immunohistochemistry, and an enzyme-linked immunosorbent assay were employed to assess liver and intestinal injury, count intestinal IgA+ plasma cells, and measure the expression level of IgA and interferon gamma (IFN-gamma) in the small intestinal mucosa of mice. RESULTS: Injured intestinal mucosa was observed in the acute liver necrosis group but not in the normal, LPS or GalN groups. Compared with the normal group, intestinal IgA+ plasma cells were slightly decreased in the LPS and GalN groups [429 +/- 20 per high power field (HPF), 406 +/- 18/HPF, respectively], whereas they were markedly decreased in the acute liver necrosis group (282 +/- 17/HPF vs 495 +/- 26/HPF in normal group, P < 0.05). The expression of intestinal IgA was also slightly decreased in LPS and GalN groups, but was markedly reduced in the acute liver necrosis group as determined by enzyme-linked immunosorbent assay (P < 0.05). In contrast, the level of IFN-gamma was slightly increased in LPS, GalN and acute liver necrosis groups, but with no statistical significance (P > 0.05). CONCLUSION: Intestinal IgA+ plasma cells and IgA expression levels indicating that mucosal immune barrier dysfunction, does exist in acute liver necrosis.


Subject(s)
Chemical and Drug Induced Liver Injury/immunology , Immunoglobulin A/metabolism , Intestine, Small/immunology , Plasma Cells/immunology , Acute Disease , Alanine Transaminase/blood , Animals , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/pathology , Disease Models, Animal , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Galactosamine , Immunity, Mucosal , Interferon-gamma/metabolism , Intestinal Mucosa/immunology , Intestine, Small/pathology , Lipopolysaccharides , Liver/pathology , Male , Mice , Mice, Inbred BALB C , Necrosis , Staining and Labeling
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