RFX5 promotes the progression of hepatocellular carcinoma through transcriptional activation of KDM4A.

Regulatory factor X-5 (RFX5) represents a key transcription regulator of MHCII gene expression in the immune system. This study aims to explore the molecular mechanisms and biological significance of RFX5. Firstly, by analyzing ENCODE chromatin immunoprecipitation (ChIP)-seq in HepG2 and TCGA RNA-seq data, we discovered lysine-specific demethylase 4A (KDM4A), also named JMJD2A, to be a major downstream target gene of RFX5. Moreover, RFX5 was verified to bind directly to the KDM4A's promoter region and sequentially promoted its transcription determined by the ChIP-PCR assay and luciferase assay. In addition, RFX5-dependent regulation of KDM4A was demonstrated in HCC. Compared with adjacent non-tumor tissues, the expression levels of KDM4A were significantly raised in HCC tumor tissues. Notably, elevated levels of KDM4A were strongly correlated with HCC patient prognosis. Functionally, KDM4A overexpression largely rescued the growth inhibitory effects of RFX5 deletion, highlighting KDM4A as a downstream effector of RFX5. Mechanistically, the RFX5-KDM4A pathway promoted the progression of the cell cycle from G0/G1 to S phase and was protective against cell apoptosis through regulation of p53 and its downstream genes in HCC. In conclusion, RFX5 could promote HCC progression via transcriptionally activating KDM4A expression.

Diagnostic Value of Serum YKL-40 Level for Coronary Artery Disease: A Meta-Analysis.

OBJECTIVE: This meta-analysis aimed to identify the value of serum YKL-40 level for the diagnosis of coronary artery disease (CAD). METHODS: Through searching the following electronic databases: the Cochrane Library Database (Issue 12, 2013), Web of Science (1945 ∼ 2013), PubMed (1966 ∼ 2013), CINAHL (1982 ∼ 2013), EMBASE (1980 ∼ 2013), and the Chinese Biomedical Database (CBM; 1982 ∼ 2013), related articles were determined without any language restrictions. STATA statistical software (Version 12.0, Stata Corporation, College Station, TX) was chosen to deal with statistical data. Standard mean difference (SMD) and its corresponding 95% confidence interval (95% CI) were calculated. RESULTS: Eleven clinical case-control studies that recruited 1,175 CAD patients and 1,261 healthy controls were selected for statistical analysis. The main findings of our meta-analysis showed that serum YKL-40 level in CAD patients was significantly higher than that in control subjects (SMD = 2.79, 95% CI = 1.73 ∼ 3.85, P < 0.001). Ethnicity-stratified analysis indicated a higher serum YKL-40 level in CAD patients than control subjects among China, Korea, and Denmark populations (China: SMD = 2.97, 95% CI = 1.21 ∼ 4.74, P = 0.001; Korea: SMD = 0.66, 95% CI = 0.17 ∼ 1.15, P = 0.008; Denmark: SMD = 1.85, 95% CI = 1.42 ∼ 2.29, P < 0.001; respectively), but not in Turkey (SMD = 4.52, 95% CI = -2.87 ∼ 11.91, P = 0.231). CONCLUSION: The present meta-analysis suggests that an elevated serum YKL-40 level may be used as a promising diagnostic tool for early identification of CAD.

CD4+CXCR5+ T cells activate CD27+IgG+ B cells via IL-21 in patients with hepatitis C virus infection.

BACKGROUND: Chronic hepatitis C virus (HCV) infection causes the skewing and activation of B cell subsets, but the characteristics of IgG+ B cells in patients with chronic hepatitis C (CHC) infection have not been thoroughly elucidated. CD4+CXCR5+ follicular helper T (Tfh) cells, via interleukin (IL)-21 secretion, activate B cells. However, the role of CD4+CXCR5+ T cells in the activation of IgG+ B cells in CHC patients is not clear. METHODS: The frequency of IgG+ B cells, including CD27-IgG+ B and CD27+IgG+ B cells, the expression of the activation markers (CD86 and CD95) in IgG+ B cells, and the percentage of circulating CD4+CXCR5+ T cells were detected by flow cytometry in CHC patients (n=70) and healthy controls (n=25). The concentrations of serum IL-21 were analyzed using ELISA. The role of CD4+CXCR5+ T cells in the activation of IgG+ B cells was investigated using a co-culture system. RESULTS: A significantly lower proportion of CD27+IgG+ B cells with increased expression of CD86 and CD95 was observed in CHC patients. The expression of CD95 was negatively correlated with the percentage of CD27+IgG+ B cells, and it contributed to CD27+IgG+ B cell apoptosis. Circulating CD4+CXCR5+ T cells and serum IL-21 were significantly increased in CHC patients. Moreover, circulating CD4+CXCR5+ T cells from CHC patients induced higher expressions of CD86 and CD95 in CD27+IgG+ B cells in a co-culture system; the blockade of the IL-21 decreased the expression levels of CD86 and CD95 in CD27+IgG+ B cells. CONCLUSIONS: HCV infection increased the frequency of CD4+CXCR5+ T cells and decreased the frequency of CD27+IgG+ B cells. CD4+CXCR5+ T cells activated CD27+IgG+ B cells via the secretion of IL-21.

Absolute quantification of serum microRNA-122 and its correlation with liver inflammation grade and serum alanine aminotransferase in chronic hepatitis C patients.

OBJECTIVES: MicroRNA-122 has been shown to be crucial for efficient HCV RNA replication in vitro. Pretreatment intrahepatic microRNA-122 levels in chronic hepatitis C (CHC) patients have been associated with the outcomes of interferon therapy. Here, we determined microRNA-122 serum levels in CHC patients and healthy donors using an absolute quantification approach and evaluated the correlation with liver inflammation grades and serum alanine aminotransferase (ALT) levels. METHODS: Serum samples were collected from 105 treatment-naive CHC patients, 11 acute hepatitis patients, and 33 healthy donors. Serum microRNA-122 was measured using the TaqMan RT-qPCR. The cycle threshold values were converted to copy numbers by drawing a standard curve using a chemical synthetic standard. For accurate quantification, copy numbers were further normalized according to the recovery ratios of spiked-in cel-miR-39. RESULTS: Serum levels of microRNA-122 were significantly higher in acute hepatitis and CHC patients than in healthy donors (p<0.001). However, there was no significant association between microRNA-122 and ALT serum levels or liver inflammation grades. CONCLUSIONS: The present study showed that serum microRNA-122 was elevated in acute and chronic hepatitis patients. However, this biomarker for acute liver injury did not reflect the liver inflammation activity in CHC patients.

In vitro interactions between rat bone marrow-derived endothelial progenitor cells and hepatic stellate cells: interaction between EPCs and HSCs.

Transplantation of bone marrow (BM)-derived endothelial progenitor cells (EPCs) has been reported to improve liver fibrosis, but there is no direct evidence for the mechanism of improvement. We investigated the mechanism in vitro by coculturing BM-derived EPCs with activated hepatic stellate cells (HSCs) to mimic the hepatic environment. EPCs and HSCs were cultured alone and indirectly cocultured at a 1:1 ratio in a Transwell system. The characteristics of HSCs and EPCs were examined at different time points. An invasion assay showed the time-dependent effect on degradation of the extracellular matrix (ECM) layer in EPCs cultured alone. Real-time PCR and enzyme-linked immunosorbent assay analysis revealed that EPCs served as a source of matrix metalloproteinase-9 (MMP-9), and MMP-9 expression levels significantly increased during the 2 d of coculture. CFSE labeling showed that EPCs inhibited proliferation of HSCs. Annexin-V/PI staining, erminal deoxynucleotidyl transferase X-dUTP nick end labeling analysis, and (cleaved) caspase-3 activity revealed that EPCs promoted HSC apoptosis. However, the proliferation and apoptosis of EPCs were unaffected by cocultured HSCs. Coculturing increased the expression of inducible nitric oxide synthase, vascular endothelial growth factor, and hepatocyte growth factor (HGF) in EPCs, promoted differentiation of EPCs, and reduced the expression of types I and III collagens and transforming growth factor beta 1. Knockdown of HGF expression attenuated EPC-induced activation of HSC apoptosis and profibrotic ability. These findings demonstrated that BM-derived EPCs could degrade ECM, promoting activated HSC apoptosis, suppressing proliferation and profibrotic ability of activated HSCs. HGF secretion by EPCs plays a key role in inducing activated HSC apoptosis and HSC profibrotic ability.

In vitro inhibition of HBV replication by a novel compound, GLS4, and its efficacy against adefovir-dipivoxil-resistant HBV mutations.

BACKGROUND: HBV infection continues to be an important worldwide cause of morbidity and mortality. Patients with chronic hepatitis B can be successfully treated using nucleoside/nucleotide analogues. However, drug-resistant HBV mutants frequently arise, leading to treatment failure and progression to liver disease. Here, we report the effects of GLS4, a non-nucleosidic inhibitor that exhibits a novel and highly specific anti-HBV activity. METHODS: The median inhibitory concentrations (IC(50)s) of GLS4 on HBV were measured by Southern blotting. HBV capsid and core protein levels were detected by immunoblotting. To determine the antiviral activity of GLS4 against adefovir dipivoxil (ADV)-resistant HBV mutants, HepG2 cells transiently transfected with PUC-HBV1.2 plasmids that contained one of three major ADV-resistant mutations (rtA181T, rtA181V and rtN236T) were treated with GLS4. Intracellular HBV replicative intermediates were detected by Southern blotting. The effect on the in vitro assembly of HBV capsid protein was examined using dynamic light scattering and electron microscopy. RESULTS: The IC(50) of GLS4 was 0.012 µM, which is significantly lower than that of lamivudine (0.325 µM). Immunoblot analysis of HepG2.2.15 cells and transiently transfected HepG2 cells indicated that GLS4 treatment interfered with the formation of core particles (assembly). The ADV-resistant HBV mutant strains were also sensitive to GLS4. Upon examining the in vitro assembly of HBV core protein 149 by electron microscopy, increased aberrant particles were observed after GLS4 treatment. CONCLUSIONS: GLS4 is a new and unique potential anti-HBV agent that possesses a different mechanism of action than existing therapeutic drugs.

Intestinal immune barrier integrity in rats with nonalcoholic hepatic steatosis and steatohepatitis.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has emerged as the major cause of chronic liver injury. Intestinal barrier plays an important role in the pathogenis of NAFLD. The aim of this article was to assess intestinal immune barrier function during the development of NAFLD. METHODS: Totally 60 male Sprague-Dawley (SD) rats were divided into 2 groups: normal diet (ND) group and high-fat diet (HFD) group. NAFLD rat model was established in the HFD rat group. Portal blood endotoxin level was assessed by limulus test. The percentage of CD4+ cells and CD8+ cells in peripheral blood mononuclear cells (PBMC) and lymphocytes in Peyer's patches (PP) were analysed by flow cytometry. Intestinal secretory immunoglobulin A (SIgA) level was evaluated by enzyme-linked immunosorbent assay. Paired Student's t test was used for the statistic analysis. RESULTS: HFD rats presented with simple steatosis at the 4th and 8th week and progressed to nonalcoholic steatohepatitis at the 12th week. Elevated lipopolysaccharides (LPS) level in HFD rats was observed at the 8th week ((1.54 ± 0.30) times of ND group, P < 0.01). CD4/CD8 ratios in PBMC and PP of HFD rats were increased at the 4th week ((1.50 ± 0.47) and (1.63 ± 0.34) times of ND group, P < 0.05) and decreased at the 8th week ((0.50 ± 0.16) and (0.61 ± 0.26) times of ND group, P < 0.05). At the 12th week, CD4/CD8 ratio ((1.47 ± 0.46) times, P < 0.05) in PP increased to levels observed in the 4th week. Intestinal SIgA expression of HFD rats was remarkably up-regulated at 12th week ((2.70 ± 1.65) times, P < 0.05). CONCLUSION: Liver-gut axis in rats with NAFLD may mediate and improve intestinal immune function by increased CD4/CD8 ratio in PP and increased production of SIgA.

Outcome of hepatitis C virus infection in Chinese paid plasma donors: a 12-19-year cohort study.

BACKGROUND AND AIMS: Commercial plasma donation was introduced in China in the 1970s. Cases of non-A, non-B hepatitis (hepatitis C) continued to occur, with multiple outbreaks among plasma donors in Guan county, Hebei province between 1972 and 1990. The outcomes of hepatitis C virus (HCV) infection in these paid plasma donors from six villages of Guan county were followed up for 12-19 years. METHODS: A total of 402 plasma donors with HCV infection were enrolled since anti-HCV-positive in 1991 or 1998. Follow up was maintained until death or the end of the observation period. No antiviral treatment was applied during the period of infection. RESULTS: Follow up was lost in 23 cases. After a 12-19-year follow up, 31 donors died, with the cause of death directly related to liver disease in 15 cases, and an overall mortality of 8.18% (31/379). The incidence of liver cirrhosis was 10.03%, and hepatocellular carcinoma (HCC) was 2.90%. The rate of viral spontaneous clearing was 20.32% (77/379), and 13.69% (23/168) in males and 25.59% (54/211) in females. In May 2010, detections were performed in 348 cases. Abnormality of liver function was related to HCV viremia. Sex and alcohol intake impacted the outcome of HCV infection. There was no correlation between the viral spontaneous clearance with age of infection and genotype. CONCLUSIONS: This area has a high rate of chronicity in HCV infection due to plasma donation. Twenty-five years after virus infection, liver cirrhosis or HCC developed in one-tenth of patients, with an overall mortality of 8.18%.

Modulation of Ca²âº signals by epigallocatechin-3-gallate(EGCG) in cultured rat hippocampal neurons.

Green tea has been receiving considerable attention as a possible neuroprotective agent against neurodegenerative disease. Epigallocatechin-3-gallate (EGCG) is the major compound of green tea. Calcium signaling has profound effects on almost all aspects of neuronal function. Using digital calcium imaging and patch-clamp technique, we determined the effects of EGCG on Ca(2+) signals in hippocampal neurons. The results indicated that EGCG caused a dose-dependent increase in intracellular Ca(2+) ([Ca(2+)](i)). This [Ca(2+)](i) increase was blocked by depleting intracellular Ca(2+) stores with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin and cyclopiazonic acid. Furthermore, EGCG-stimulated increase in [Ca(2+)](i) was abolished following treatment with a PLC inhibitor. However, EGCG inhibited high-voltage activated Ca(2+) currents (I(HVA)) and NMDA-induced inward currents (I(NMDA)). These data suggest that EGCG triggers a cascade of events: it activates phospholipase C (PLC), mobilizes intracellular Ca(2+) stores, raises the cytosolic Ca(2+) levels, and inhibits the VGCC and NMDA receptors-mediated Ca(2+) influx through a process that remains to be determined.

Inhibitory effect of human interferon-beta-1a on activated rat and human hepatic stellate cells.

BACKGROUND AND AIMS: Hepatic stellate cells (HSC) are the primary cell type mediating hepatic fibrosis. Although known for its antiviral effects, the inhibitory effects of interferon-beta (IFN-ß) on HSC treatment have not yet been established. METHODS: Both human and rat activated HSC cell lines were incubated with increasing concentrations of recombinant human IFN-ß1a (rhIFN-ß1a) for 24, 48 or 72 h. The effects of rhIFN-ß1a on α-smooth muscle actin (α-SMA), collagen types I and III, transforming growth factor-ß1 (TGF-ß1), platelet-derived growth factor-BB (PDGF-BB), and mothers against decapentaplegic homolog (Smad4, Smad7) expression in HSC were examined using Western blotting and immunocytochemistry. Proliferation of HSC was evaluated via bromodeoxyuridine assay. RESULTS: rhIFN-ß1a treatment had a dose-dependent, inhibitory effect on α-SMA and collagen type I protein expression. In addition, rhIFN-ß1a decreased the expression of collagen type III, TGF-ß1, PDGF-BB and Smad4 protein expression in HSC compared with untreated cells. We also observed increased Smad7 protein expression and decreased proliferation in rhIFN-ß1a-treated HSC. CONCLUSIONS: Our data suggest that rhIFN-ß1a treatment decreased α-SMA and collagen expression and inhibited the activation of HSC through the inhibition of the TGF-ß and PDGF pathways.

Regulatory T cell depletion enhances tumor specific CD8 T-cell responses, elicited by tumor antigen NY-ESO-1b in hepatocellular carcinoma patients, in vitro.

Immunotherapy in hepatocellular carcinoma based on one or a few tumor specific antigens have shown limited antitumor efficacy. As a major suppressive factor in tumor immune response, better understanding of the role of regulatory T cells (Tregs) in hepatocellular carcinoma might be important for design of future immunotherapy-based clinical protocols. Tregs from 49 HCC patients and 40 controls were identified by flow cytometric analysis for the phenotype. Functional studies were performed by analyzing their inhibition to immune responses. Finally investigating whether elimination of Tregs was capable of enhancing the immunostimulatory efficacy of NY-ESO-1b peptides. In HCC peripheral blood and tumor-infiltrating lymphocytes, we found increased numbers of Tregs, which expressed high levels of HLA-DR, GITR and CD103. The prevalence of Tregs increased with during progressive stages in HCC patients. Moreover, the elimination of Treg cells followed by stimulating with NY-ESO-1b peptide significantly improved the anti-tumor cytotoxic T lymphocytes responses in HCC patients compared with stimulating with NY-ESO-1b peptide alone. The immune response efficiency increased from 37.5 to 62.5%. In conclusion, the increase in frequency of Treg cells might play a role in suppression of the immune response against HCC and for the design of immunotherapy the incorporation of the Treg cell depletion strategy will achieve potent anti-tumor immunity with therapeutic impact.

PI3K integrates the effects of insulin and leptin on large-conductance Ca2+-activated K+ channels in neuropeptide Y neurons of the hypothalamic arcuate nucleus.

The adipocyte-derived hormone leptin and the pancreatic beta-cell-derived hormone insulin function as afferent signals to the hypothalamus in an endocrine feedback loop that regulates body adiposity. They act in hypothalamic centers to modulate the function of specific neuronal subtypes, such as neuropeptide Y (NPY) neurons, by modifying neuronal electrical activity. To investigate the intrinsic activity of these neurons and their responses to insulin and leptin, we used a combination of morphological features and immunocytochemical technique to identify the NPY neurons of hypothalamic arcuate nucleus (ARC) and record whole cell large-conductance Ca(2+)-activated potassium (BK) currents on them. We found that both of the hormones increase the peak amplitude of BK currents, shifting the steady-state activation curve to the left. The effect of both insulin and leptin can be prevented by pretreatment with inhibitors of tyrosine kinase and phosphatidylinositol 3-kinase (PI3K) but not MAPK. These data indicate that PI3K-mediated signals are the common regulators of BK channels by insulin and leptin and mediated the two hormones' identical activatory effects on ARC NPY neurons. The effect of insulin and leptin together was similar to that of insulin or leptin alone, and leptin or insulin pretreatment did not lead to insulin- or leptin-sensitizing effects, respectively. These intracellular signaling mechanisms may play key roles in regulating ARC NPY neuron activity and physiological processes such as the control of food intake and body weight, which are under the combined control of insulin and leptin.

Activation of phosphatidylinositol-linked novel D1 dopamine receptors inhibits high-voltage-activated Ca2+ currents in primary cultured striatal neurons.

Recent evidences indicate the existence of a putative novel phosphatidylinositol (PI)-linked D(1) dopamine receptor that mediates excellent anti-Parkinsonian but less severe dyskinesia action. To further understand the basic physiological function of this receptor in brain, the effects of a PI-linked D(1) dopamine receptor-selective agonist 6-chloro-7,8-dihydroxy-3-methyl-1-(3-methylphenyl)-2,3,4,5-tetrahydro-1H-3-benzazepine (SKF83959) on high-voltage activated (HVA) Ca(2+) currents in primary cultured striatal neurons were investigated by whole cell patch-clamp technique. The results indicated that stimulation by SKF83959 induced an inhibition of HVA Ca(2+) currents in a dose-dependent manner in substance-P (SP)-immunoreactive striatal neurons. Application of D(1) receptor, but not D(2), alpha(1) adrenergic, 5-HT receptor, or cholinoceptor antagonist prevented SKF83959-induced reduction, indicating that a D(1) receptor-mediated event assumed via PI-linked D(1) receptor. SKF83959-induced inhibitory modulation was mediated by activation of phospholipase C (PLC), mobilization of intracellular Ca(2+) stores and activation of calcineurin. Furthermore, the inhibitory effects were attenuated significantly by the L-type calcium channel antagonist nifedipine, suggesting that L-type calcium channels involved in the regulation induced by SKF83959. These findings may help to further understand the functional role of the PI-linked dopamine receptor in brain.

Activation of phosphatidylinositol-linked novel D1 dopamine receptor contributes to the calcium mobilization in cultured rat prefrontal cortical astrocytes.

Recent evidences indicate the existence of an atypical D(1) dopamine receptor other than traditional D(1) dopamine receptor in the brain that mediates PI hydrolysis via activation of phospholipase C(beta) (PLC(beta)). To further understand the basic physiological function of this receptor in brain, the effects of a selective phosphoinositide (PI)-linked D(1) dopamine receptor agonist SKF83959 on cytosolic free calcium concentration ([Ca(2+)](i)) in cultured rat prefrontal cortical astrocytes were investigated by calcium imaging. The results indicated that SKF83959 caused a transient dose-dependent increase in [Ca(2+)](i). Application of D(1) receptor, but not D(2), alpha(1) adrenergic, 5-HT receptor, or cholinergic antagonist prevented SKF83959-induced [Ca(2+)](i) rise, indicating that activation of the D(1) dopamine receptor was essential for this response. Increase in [Ca(2+)](i) was a two-step process characterized by an initial increase in [Ca(2+)](i) mediated by release from intracellular stores, supplemented by influx through voltage-gated calcium channels, receptor-operated calcium channels, and capacitative Ca(2+) entry. Furthermore, SKF83959-stimulated increase in [Ca(2+)](i) was abolished following treatment with a PLC inhibitor. Overall, these results suggested that activation of D(1) receptor by SKF83959 mediates a dose-dependent mobilization of [Ca(2+)](i) via the PLC signaling pathway in cultured rat prefrontal cortical astrocytes.

[Construction of eukaryotic expression vector expressing hepatitis B virus HBsAg and EGFP fusion protein and establishment of stable transfected Chang Liver cell line].

OBJECTIVE: To construct a eukaryotic expression vector for expressing hepatitis B virus (HBV) recombinant HBsAg-EGFP fusion protein and obtain a stable transfected Chang Liver cell line. METHODS: The coding region of HBsAg gene of HBV was amplified by PCR and was digested by BamH I/EcoR I . This fragment was inserted into pEGFPN1 with T4 ligase and transformed E-coli TG1. The positive recombinant plasmid was selected, then the recombinant plasmid was transfected into Chang Liver cell by Lipofectamine 2000 cells containing stable transformants were selected by the ability of resistance to G418 and isolated with a limited dilution. The stable transfected cell line expressing high level HBsAg-EGFP fusion protein was obtained. RESULTS: The eukaryotic expression vector named pEGFPN1-HBsAg was successfully constructed and the stable transfected Chang Liver cell line expressing pEGFPN1-HBsAg fusion protein was obtained. CONCLUSION: The stable transfected Chang Liver cell line could express pEGFPN1-HBsAg fusion protein, could be used to screen the proteins differentially expressed in HBsAg expression Chang Liver cells, which brought some new clues for studying the potential molecular mechanism of HBsAg protein.

Redox modulation of long-term potentiation in the hippocampus via regulation of the glycogen synthase kinase-3beta pathway.

Alzheimer disease (AD) is an age-related neurodegenerative disorder. Many observations indicate that impaired redox regulation is implicated in AD with synaptic failure. The aim of the current investigation was to characterize the role of redox-active agents on long-term potentiation (LTP) in the CA1 region of rat hippocampal slices and to elucidate the molecular sequence of events leading to these changes. The results presented here indicate that the membrane-permeable oxidizing agent chloramine-T (CH-T) inhibits the induction of LTP, whereas the membrane-permeable reducing agent dithiothreitol (DTT) enhances the induction of LTP. In contrast, neither the membrane-impermeable oxidizing agent 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB) nor the membrane-impermeable reducing agent tris-(2-carboxyethyl) phosphine (TCEP) can affect the induction of LTP. The inhibition of LTP by CH-T can be restored by pretreatment with DTT but not with TCEP, whereas the enhancement of LTP by DTT can be reversed by pretreatment with CH-T but not with DTNB. We also provide evidence that the CH-T-evoked inhibition of LTP is mediated via activation of glycogen synthase kinase-3beta (GSK-3beta), whereas the DTT-evoked enhancement of LTP is mediated via inactivation of GSK-3beta. These findings will benefit the understanding of the redox contribution to the mechanisms underlying synaptic plasticity and AD pathogenesis.

Senescence marker protein 30 in acute liver failure: validation of a mass spectrometry proteomics assay.

BACKGROUND: Our previous proteomic study showed that the senescence marker protein (SMP30) is selectively present in the plasma of a murine model of acute liver failure (ALF). The aim of this study was to validate this SMP30 expression in the plasma and liver tissues of mice and humans with ALF. METHODS: After the proteomic analysis of plasma from a murine model of D-galactosamine/lipopolysaccharide (GalN/LPS)-induced ALF by two-dimensional electrophoresis (2-DE) and mass spectrometry, the expression levels of SMP30 in the plasma and liver tissues were validated by western blot and RT-PCR analyses. These results were then confirmed in plasma samples from humans. RESULTS: These data validate the results of 2-DE, and western blot showed that SMP30 protein levels were only elevated in the plasma of ALF mice. Further analysis revealed that GalN/LPS induced the downregulation of SMP30 protein levels in liver tissues (by approximately 25% and 16% in the GalN/LPS-treated mice and in the treated mice that survived, respectively; P < 0.01). Hepatic SMP30 mRNA levels decreased by about 90% only in the mice that survived the GalN/LPS treatment. Importantly, plasma obtained from patients with ALF also contained higher levels of SMP30, about (3.65 +/- 0.34) times those observed in healthy volunteers. CONCLUSION: This study shows that SMP30 is not only a potential biomarker for the diagnosis and even prognosis of ALF. It also plays a very important role in a self-protective mechanism in survival and participates in the pathophysiological processes of ALF.

Role of ISGF3 in modulating the anti-hepatitis B virus activity of interferon-alpha in vitro.

BACKGROUND AND AIM: Although interferon-alpha (IFN-alpha) is an effective treatment for hepatitis B virus (HBV) infection, its precise mechanism of action has not been identified. In this study, we investigated the role of signal transduction pathways in the activation of anti-HBV responses mediated by IFN-alpha. METHODS: Using an oligo microarray, we found that four genes in the IFN-alpha signal pathway were markedly upregulated by IFN-alpha in human hepatoma cells regardless of whether they had been transfected with a plasmid containing the HBV genome: signal transducers and activators of transcription 1 (STAT1), interferon regulatory factor-9 (IRF-9, also called ISGF3gamma or P48), IFN-alpha-inducible protein 15 (IFI-15) and IFN-alpha-inducible protein 6-16 (IFI-6-16). We also investigated the role of IFN-stimulated gene factor3 (ISGF3) complex in IFN-alpha-mediated anti-HBV responses in human hepatoma cells by measuring the mRNA of the three genes within ISGF3 (STAT1, STAT2 and IRF-9) using semiquantitative reverse-transcription PCR (RT-PCR), and expression of the three proteins by western blot, and the mRNA and protein of dsRNA-dependent protein kinase (PKR). RESULTS: STAT1, STAT2, IRF-9 and PKR mRNA as well as protein levels were upregulated by IFN-alpha treatment. When cells were pretreated with genistein, STAT1, STAT2 and IRF-9 mRNA levels remained unchanged after IFN-alpha stimulation, but PKR mRNA levels decreased, and the expression of the STAT1, P-STAT2, IRF-9 and PKR proteins decreased. Levels of HBV DNA decreased in the supernatants of cells treated with IFN-alpha, while ISGF3 levels increased. The quantity of HBV DNA remained unchanged by pretreating with genistein. CONCLUSIONS: These observations suggested that the Janus tyrosine kinase-STAT (JAK-STAT) pathway may play a major role in mediating the effects of IFN-alpha against HBV, and that ISGF3 might be a key factor.

Identification of novel molecular candidates for acute liver failure in plasma of BALB/c murine model.

In an effort to identify proteins involved in the disease process of acute liver failure (ALF), we investigated changes in the plasma proteome associated with d-galactosamine/lipopolysaccharide (GalN/LPS) treatment of BALB/c mice. The plasma samples from mice with ALF and control were screened for potential differences using two-dimensional electrophoresis followed by liquid chromatography-electrospray ionization-tandem mass spectrometry or matrix associated laser desorption ionization-time-of-flight mass spectrometry. The expression levels of candidate protein named phosphatidylethanolamine binding protein (PEBP) in plasma and liver, brain tissues were confirmed by western blot and RT-PCR analyses. Results were confirmed in plasma samples of human beings. Seven proteins existed in plasma of GalN/LPS-treatment animals only but not in controls. They included PEBP, regucalcin, Cu/Zn superoxide dismutase, glyoxalase 1, malate dehydrogenase, proteasome subunit alpha type 1, and HPMS haptoglobin precursor. Two proteins, proteasome subunit alpha type 5 and apolipoprotein A-I precursor, were up-regulated by GalN/LPS, and one protein, HPMS haptoglobin precursor, was down-regulated by this treatment. Western blot analysis confirmed the results that PEBP protein levels increased significantly in plasma and liver tissues only in ALF mice, but not in surviving mice treated with GalN/LPS. Further analysis revealed that GalN/LPS also induced up-regulation of PEBP mRNA levels in liver tissues. Importantly, plasma obtained from ALF patients, but not from healthy volunteers or from hepatitis patients, also contained detectable levels of PEBP. The present study show that PEBP may be a potential plasma biomarker for ALF diagnosis and participate in the pathphysiological process of ALF.

[Effect of glia maturation factor beta on the activation of hepatic stellate cells and on liver fibrosis].

OBJECTIVE: To further study the mechanism of the inhibitory effect of interferon beta-1a (IFN beta-1a) on the activation of human hepatic stellate cell (HSC) LX-2, and to analyze the differences on the protein expression in LX-2 induced by I IFN beta-1a. METHODS: Cultured LX-2 cells were treated with 2000 U/ml IFN beta-1a for 48 h. Two-dimensional gel electrophoresis (2-DE) was performed to compare protein patterns of the control (untreated) and IFN beta-1a treated LX-2 and for quantitative and qualitative analyses of protein expression. A rat liver fibrosis model was established and the rats were sacrificed and their various tissues were obtained for the same analyses. Western blotting and RT-PCR were used to validate the expression of the changed proteins after treatment of IFN beta-1a in LX-2 cells and of various tissues of the rats. RESULTS: 708 +/- 25 spots were detected in control LX-2 cells and 804 +/- 32 spots in IFN beta-1a-treated LX-2 cells. A match rate of 73%-82% was achieved. The results also showed that 31 protein spots displayed quantitative changes in expression after IFN beta-1a treatment. Of the 31 spots, 21 proteins were identified, of which, one was newly found, two were enhanced in abundance and 18 showed lower expressions. The newly found protein was glia maturation factor beta (GMF beta). The treatment of LX-2 with IFN beta-1a increased the production of GMF beta(GMF beta) protein in comparison with the untreated cells (t=1.81, P < 0.01). The expression of GMF beta protein (1.81 vs 0.10) and mRNA (0.85 vs 0.12) were more in the normal liver tissues than in the cirrhotic liver tissues (t=2.53, 2.13 respectively, P < 0.01). The expressions of GMF beta protein and mRNA were weak in rat heart and lung tissues, however, they were strong in rat liver, kidney, spleen and brain tissues (t=1.91, 1.94 respectively, P < 0.01). CONCLUSION: There is a significant difference of protein expression levels between IFN beta-1a untreated and treated LX-2 cells. These proteins, especially GMF beta, may be involved in an inhibition process of IFN beta-1a on activation and apoptosis of LX-2 cells. This proteome study may be useful in further studies of the relationship of IFN beta-1a treatment and human liver diseases.