Effects of PPAR-alpha activation on oleic acid-induced steatosis and expression of heme oxygenase-1 in HepG2 cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effects of peroxisome proliferator activated receptor-alpha (PPAR-a) activation on oleic acid (OA)-induced steatosis and hepatic expression of heme oxygenase-1 (HO-1) using an in vitro cell model system.</p><p><b>METHODS</b>A steatosis human hepatocyte in vitro model system was established by treating HepG2 cells with 0.2 mmol/L of oleic acid for 24 hours. The steatosis cells were then divided into four groups for an additional 24 hours of treatment with 0.2 mmol/L of oleic acid alone (model control group) or with 5, 10 or 50 pnol/L of fenofibrate (FF, a selective PPAR-a agonist; experimental groups). Untreated HepG2 cells served as non-steatosis controls. Effect of PPAR-a activation on fat accumulation was detected by Oil Red O staining and on intracellular triglyceride (TG) levels by enzymatic assay. mRNA and protein expression of PPAR-alpha and HO-1 were quantified by real-time PCR and immunocytochemistry, respectively. One-way ANOVA and the LSD t-test were used for between-group comparisons, and correlation analysis was performed with the Pearson's correlation coefficient.</p><p><b>RESULTS</b>The steatosis model control cells showed significantly increased TG deposition (379.98 +/- 23.19 mg/g protein, vs. non-steatosis controls F = 148.56, P< 0.01), significantly decreased mRNA and protein expression of PPAR-alpha (0.42 +/- 0.38,F= 177.64,P< 0.01 and 0.47 +/- 0.14, F= 120.76,P< 0.01) and HO-1 (0.36 +/- 0.66, F= 74.77,P< 0.01 and 0.26 +/- 0.10,F= 119.90,P<0.01). FF (5, 10 and 50 micromol/L) inhibited the steatosis induced by OA in a concentration-dependent manner (294.00 +/- 19.80, 250.33 +/- 9.96, and 196.99 +/- 9.14, F = 148.56, P <0.01) and increased the mRNA and protein expression of PPAR-alpha (0.55 +/- 0.65, 0.85 +/- 0.61, and 1.31 +/- 0.36,F= 177.64,P< 0.01; 0.82 + 0.11, 1.31 +/- 0.16, and 1.75 +/- 0.13, F= 120.76,P <0.01) and HO-1 (0.62 +/- 0.05, 0.84 +/- 0.07, and 1.30 +/- 0.11,F= 74.77,P <0.01; 0.44 +/- 0.08, 0.81 +/- 0.08, 1.20 +/- 0.10,F= 119.90,P< 0.01).</p><p><b>CONCLUSION</b>Activation of PPAR-a prevents OA-induced steatosis in HepG2 cells, and HO-1 may function as a downstream effector of this mechanism.</p>

Comparative analysis of the efficacies of entecavir capsules and lamivudine in chronic hepatitis B patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the efficacy profile of entecavir capsule (ETV) as a chronic hepatitis B therapy, as compared to lamivudine (LAM).</p><p><b>METHODS</b>In this multicenter, randomized, double-blind, parallel group evaluation of ETV, 232 subjects were administered a 96-week course of 0.5 mg/day ETV or 100 mg/day LAM. PCR measurement of hepatitis B virus (HBV) was conducted throughout the treatment course to determine achievement of complete virologic response (CVR; defined as less than 500 copies/ml of HBV DNA) or experience of virology rebound ( more than 500 copies/ml of HBV DNA after achievement of CVR).</p><p><b>RESULTS</b>After week-48 of treatment, the ETV group showed a higher CVR rate (90.3% vs. LAM: 59.4%) and lower virology rebound rate (1.9% vs. LAM: 13.9%). After week-96 of treatment, the ETV group continued to have a higher CVR rate (86.0% vs. LAM: 71.4%), and virology rebound was experienced by significantly less subjects in the ETV group (1.2% vs. LAM: 11.9%, P = 0.005).</p><p><b>CONCLUSION</b>ETV therapy can quickly and continuously suppress HBV replication in chronic hepatitis B patients, and has a lower resistance rate than LAM. Compared to LAM, ETV may be a superior long-term treatment choice for chronic hepatitis B.</p>

Effects of antihistamine treatment on immune function in rats with experimental hepatitis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effects of antihistamine treatment on immune function in rats with experimental hepatitis.</p><p><b>METHODS</b>Thirty Wistar rats were randomly allocated into three groups:experimental hepatitis group (EH group), antihistamine treatment group (AH group) and normal control group (NC group). Rats in the EH group received the subcutaneous injection of 40% carbon tetrachloride oil solution and were fed on diet with low-protein, low-choline, high-fat and high-alcohol,while rats in the AH group received antihistamine treatment(ketotifen + vitamin C) additionally.They were sacrificed after 4 weeks, and the levels of serum alanine aminotransferase(ALT), total bilirubin (TBil), histamine(HA), IFNgamma, IL-12, IL-4 and IL-10 were determined. The levels of IL-12 mRNA and IFN-gamma mRNA in liver tissue were determined via real-time reverse transcriptional polymerase chain reaction(RT-PCR).</p><p><b>RESULTS</b>(1) Compared to the NC group, in the EH group, the levels of ALT, TBil, and circulating and intrahepatic HA were significantly increased(P less than 0.05); intrahepatic HA were significantly decreased(P less than 0.05) after antihistamine treatment. (2) Compared to the NC group, in the EH group, the levels of IL-4, IL-10 were significantly increased((0.504+/-0.202)ng/ml and (29.025+/-1.478) pg/ml vs (0.811+/-0.244)ng/ml and (33.72+/-4.293)pg/ml respectively, P less than 0.05), and the levels of IL-12 were decreased ((6.515+/-2.893)pg/ml vs (3.519+/-1.113)pg/ml, P less than 0.05); and after antihistamine treatment the levels of IL-4 and IL-10 were significantly decreased (were (0.423+/-0.168)ng/ml and (30.412+/-3.275)pg/ml, P less than 0.05), the levels of IL-12 were significantly increased (P less than 0.05), but the level of IFNgamma had no significance (P more than 0.05). The levels of intrahepatic IL-12 mRNA and IFNgamma mRNA had similar results.</p><p><b>CONCLUSION</b>Antihistamine treatment may improve liver function and correct Th1/Th2 unbalance.</p>

Changes in mast cells and hepatic expression of c-kit and stem cell factor in the rat model of chronic hepatitis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the potential role of mast cells and the related molecular mechanism in chronic hepatitis (CH) using a rat model system.</p><p><b>METHODS</b>Thirty Wistar rats (15 males, 15 females; weight range: 230-290 g) were randomly divided into the normal contrast (NC) group and experimental CH group. The CH group received subcutaneous injection of CCl4 and a diet high in cholesterol and alcohol content and low in protein and choline content. Throughout the 4-week modeling period, aseptic blood samples were taken to test plasma tryptase (TS) and hyaluronic acid (HA) levels. The rats were euthanized to assess the changes in liver mast cells by histology and morphology analyses and the changes in liver expression of c-kit and stem cell factor (SCF) proteins by immunohistochemistry and mRNAs by RT-PCR.</p><p><b>RESULTS</b>Compared to the NC group, the CH group had higher plasma and liver concentration of HA (78.09 +/- 38.55 vs. 145.14 +/- 52.54 ng/ml, 51.58 +/- 20.45 vs. 106.59 +/- 43.15 ng/100 mg; t = 2.457 and 2.825 respectively, both P less than 0.05) and TS (0.416 +/- 0.143 vs 0.753 +/- 0.210 mg/ml; t = 4.165, P less than 0.05). The CH group also showed fatty degeneration and fibrosis with many degranulating and degranulated mast cells filled with purple granula located around the liver blood vessels and in fiber-intervals. The CH livers also showed a significantly higher number of mast cells (2.167 +/- 0.924 vs. NC: 10.92 +/- 1.575; t = 7.633, P less than 0.05) and stronger intensity of c-kit staining (2.783 +/- 0.577 vs. 12.86 +/- 3.126; t = 9.511, P less than 0.05) and SCF staining (3.383 +/- 1.583 vs. 15.58 +/- 6.431; t = 9.625, P less than 0.05). The expressions of c-kit and SCF were positively correlated with HA level (r = 0.478 and 0.556 respectively, both P less than 0.05). The c-kit and SCF mRNA expression levels were also significantly higher in the CH liver tissues.</p><p><b>CONCLUSION</b>Mast cell degranulation and histamine release is significantly increased under conditions of chronic hepatitis, and the related mechanism may involve up-regulation of the membrane receptor c-kit and its ligand SCF.</p>

Effect of reduced glutathione on proliferation of rat hepatic stellate cells and the Nrf2/HO-1 signaling pathway / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the effects of reduced glutathione (GSH) on the proliferation of hepatic stellate cells and the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway.</p><p><b>METHODS</b>The rat HSC-T6 cell line was activated by lipopolysaccharide (LPS; 0.1 mug/ml) and incubated with various concentrations of GSH (0, 1, 2, 5 and 10 mmol/L) for 24 h. Cell proliferation was evaluated by the MTT colorimetric assay. Collagen IV and hyaluronic acid (HA) contents were measured by chemiluminescence immunoassay of cell supernatants. Nrf2 and HO-1 protein expression was observed by immunohistochemistry. Nrf2 and HO-1 mRNA expression was assessed by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). HO-1 activity was analyzed by spectrophotometer.</p><p><b>RESULTS</b>GSH treatment inhibited HSC-T6 proliferation and decreased the secretion of HA and collagen IV (P less than 0.05); GSH treatment of HSC-T6 cells also led to increased expression of Nrf2 and HO-1, and increased activity of HO-1 (P less than 0.05).</p><p><b>CONCLUSION</b>GSH can inhibit the proliferation of hepatic stellate cells in vitro and reduce secretion of hyaluronic acid and collagen IV. The underlying mechanism in HSC-T6 cells may involve regulation of the Nrf2/HO-1 signaling pathway.</p>

Effects of lipopolysaccharide on the maturation and secretion of human peripheral dendritic cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effects of Lipopolysaccharide (LPS) on the maturation and secretion of human peripheral dendritic cells (DCs).</p><p><b>METHODS</b>DCs from healthy human peripheral monocytes (PBMCs) were induced in vitro with rhGM-CSF, rhIL-4, Flt3-L and TNFalpha. The subjects were divided into 3 groups: the long-term group stimulated with LPS 1 microg/ml at day 1, 4, 7, 9 post culture; the short-term group stimulated with LPS 1 microg/ml at day 7 and 8 post culture, and the DCs without LPS stimulation was control group. After 10 days of culture, the morphologic features of DCs were observed by light and electron microscopes, the phenotypic patterns were characterized by flow cytometry, the proliferation of T cell were evaluated with mixed leukocytes reaction (MLR) and the levels of IL-12 and IFNgamma produced by DCs were analyzed with ELISA.</p><p><b>RESULTS</b>Compared with the short-term group, the expressions of HLA-DR (65.81%+/-10.96%), CD86 (48.81%+/-18.13%), CD80 (13.56%+/-5.48%), CD83 (11.52%+/-5.09%), the secretions of IFNgamma(15.60+/-5.83 pg/ml) and IL-12 (51.77+/-11.02 pg/ml) by the DCs in long-term group were decreased obviously (P is less than 0.05) and the proliferation of homogenic lymphocyte cells (1.548+/-0.365) stimulated by DCs was also impaired (P < 0.05).</p><p><b>CONCLUSION</b>Long-term LPS stimulation can suppress the maturation and secretion of DCs, which might be the reason of poor immunity in the patients with intestinal endotoxemia.</p>

Early prediction of lamivudine response in e antigen-negative chronic hepatitis B patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To evaluate the effects of ALT, HBsAg and HBV DNA at the baseline, 4 and 12 weeks after lamivudine treatment on the long term (104 weeks) response in e antigen-negative chronic hepatitis B patients.</p><p><b>METHODS</b>127 adult e antigen-negative chronic hepatitis B patients were enrolled in this study. All patients received treatment on LAM 100 mg/d for at least 104 weeks. The liver function, serum HBV markers and HBV viral load were regularly checked during the treatment. The effects of ALT, HBsAg and HBV DNA at the baseline, 4 and 12 weeks after lamivudine treatment on the response at 104 weeks were statistically analyzed.</p><p><b>RESULTS</b>The proportion of patients with serum HBV DNA less than 1000 copies / ml at 104 weeks after LAM treatment was 50.0% and 86.8% in patients with baseline ALT less than 5 ULN and ALT is more than or equal to 5 ULN, respectively (P less than 0.01). In patients with baseline HBsAg less than 2000 COI and HBsAg is more than or equal to 2000 COI, the proportion of patients with serum HBsAg less than 500 COI at 104 weeks after LAM treatment was 19.1% and 17.5%, respectively (P more than 0.05). the HBsAg serological conversion rates were respectively 2.1% and 2.5% , respectively (P more than 0.05), the proportion of patients with serum HBV DNA less than 1000 copies/ml was 61.7% and 67.5%, respectively (P more than 0.05). In patients with baseline HBV DNA less than 10(6) copies/ml and HBV DNA is more than or equal to 10(6) copies/ml, the proportion of patients with HBV DNA less than 1000 copies/ml were statistically different at 4 weeks and 12 weeks after treatment, however, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after LAM treatment was 62.7% and 67.1%, respectively (P more than 0.05). In patients with HBV DNA less than 1000 copies/ml and HBV DNA is more than or equal to 1000 copies/ml at 4 weeks after treatment, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after LAM treatment was 70.7% and 60.9%, respectively (P more than 0.05). In patients with HBV DNA less than 1000 copies/ml and HBV DNA is more than or equal to 1000 copies/ml at 12 weeks after treatment, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after treatment was 78.8% and 38.1%, respectively (P less than 0.01).</p><p><b>CONCLUSION</b>e antigen negative chronic hepatitis B patients with baseline ALT is more than or equal to 5 ULN and HBV DNA less than 1000 copies/ml at 12 weeks after treatment have better virological response at 104 weeks after LAM treatment. The baseline HBsAg and HBV DNA load are associated with the virological response at 104 weeks after LAM treatment.</p>

Protein expression and function of gene 2 transregulated by hepatitis B virus pre-s1 protein and its cloning / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To screen proteins in leukocytes interacting with PS1TP2 by yeast-two hybrid and to view their subcellular localization in HepG2 cells.</p><p><b>METHODS</b>The function and structure of PS1TP2 were studied by bioinformatic analysis. PS1TP2 gene was amplified and cloned into plasmid pET32a (+) and pGBKT7 to construct recombinant expression vectors pET32a (+)-PS1TP2 and pGBKT7-PS1TP2. They were transduced into E. coli Rosetta strain and yeast AH109. The transformed yeast mated with yeast Y187 containing leukocyte cDNA library plasmid in a 2xYPDA medium. Diploid yeast cells were plated on a synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) for selecting twice and then screening. Then a green fluorescent protein (GFP) expression vector pEGFP-C1-PS1TP2 was established, transduced into HepG2, and its subcellular localization was studied by fluorescence microscopy and confocal microscopy.</p><p><b>RESULTS</b>Bioinformatic analysis showed that the PS1TP2 gene was located at 6q24.1, the protein was unstable and the aliphatic index was very high. After transformation of the E. coli and yeast AH109, the expression protein showed: (1) the molecular weight of the expressed product was about 41000 Da, and (2) PS1TP2 existed within the cells. Diploid yeast cells were plated on the synthetic dropout nutrient medium containing X-a-gal for selecting twice and then screening. Twenty-six colonies from blue colonies were sequenced, pEGFP-C1-PS1TP2 was successfully expressed in the HepG2 cells, and PS1TP2 was located in the cell plasma.</p><p><b>CONCLUSION</b>A prokaryotic expression vector pET32a(+)-PS1TP2 was constructed successfully and the PS1TP2 was successfully expressed in the yeast system. Genes of PS1TP2 interact with leukocyte proteins. These results bring some new clues for studying the biological functions of HBV.</p>

Specific T-cell responses to Mycobacterium tuberculosis protein ESAT-6 in Chinese HIV positive individuals / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To detect TB specific T cell responses by using the recombinant ESAT-6 protein as stimulus in Chinese HIV infected patients.</p><p><b>METHODS</b>ELISPOT-IFN-gamma assay by using the recombinant ESAT-6 protein as stimulus to detect specific T cell responses in HIV+ patients with or without clinical manifestation of TB diseases.</p><p><b>RESULTS</b>Recombinant ESAT-6 protein specific T cell responses show significant high frequencies in both of TB patients with or without HIV infection than that in the healthy control and HIV+ group without clinical TB diseases.</p><p><b>CONCLUSION</b>The ELISPOT-IFN-gamma assay by using recombinant ESAT-6 protein as stimulus could be used in diagnoses of TB infection in Chinese HIV infected patients.</p>

Expression of human gene 5 transactivated by pre-S1 protein of hepatitis B virus in yeast cell / 中华传染病杂志

Objective To study the exact function of human gene 5 transactivated by pre-S1 protein of hepatitis B virus(PS1TP5)by investigating the gene expression of PS1TP5 in yeast cells. Methods Reverse transcription-polymerase chain reaction(RT-PCR)was performed to amplify the gene of PS1TP5 using the mRNA of HepG2 cells as template and the gene was cloned into pGEM-T vector.The gene of PS1TP5 was cut from pGEM-T-PS1TP5 vector and cloned into yeast expressive plasmid pGBKT7,then pGBKT7-PS1TP5 was transformed into yeast cell AH109.The yeast protein was isolated and analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Western hybridization.Results PS1TP5 gene was successfully amplified and identified by DNA sequencing.The digested fragment was cloned into pGBKT7 vector and transformed into yeast cell AH109.The results of SDS-PAGE and Western assay showed that the relative molecular weight of the expressed product was about 36 950,and PS1TP5 protein existed in yeast cells.Conclusion The findings suggest that PS1TP5 can be successfully expressed in yeast cell.

Epidemiology and clinical characteristics of epidemic encephalitis B in Yuncheng area of Shanxi Province / 中华传染病杂志

Objective To analyze the epidemiology and clinical characteristics of epidemic encephalitis B in Yuneheng area of Shanxi Province in 2006.Methods Seventy-nine cases diagnosed with epidemic encephalitis B were enrolled in this study and correlated data,epidemic and clinical characteristics,laboratory examinations and treatment outcome were analyzed.Results Sixty-two of 79 patients(78.5%)were middle-aged or old people,all cases(100%)occurred in July,August and September,69 cases(87.3%)were peasants.All patients(100%)had fever,73(92.4%)had conscious disturbance,27(34.2%)had respiratory failure.Encephalitis B specific IgM antibody was examined and 40 cases(85.1%)were positive.Twenty cases(25.3%)had complications.When they were discharged,37 cases(46.8%)recovered completely,14 cases(17.7%)died,12 were improved and 16 were voluntarily discharged,7 cases(8.9%)left more or less neurological deficits. Conclusion The epidemiology and clinical characteristics are important basis to diagnose epidemic encephalitis B.

Screening of genes for proteins interacting with the PS1TP5 protein of hepatitis B virus: probing a human leukocyte cDNA library using the yeast two-hybrid system / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The hepatitis B virus (HBV) genome includes S, C, P and X regions. The S region is divided into four subregions of pre-pre-S, pre-S1, pre-S2 and S. PS1TP5 (human gene 5 transactivated by pre-S1 protein of HBV) is a novel target gene transactivated by the pre-S1 protein that has been screened with a suppression subtractive hybridization technique in our laboratory (GenBank accession: AY427953). In order to investigate the biological function of the PS1TP5 protein, we performed a yeast two-hybrid system 3 to screen proteins from a human leukocyte cDNA library interacting with the PS1TP5 protein.</p><p><b>METHODS</b>The reverse transcription polymerase chain reaction (RT-PCR) was performed to amplify the gene of PS1TP5 from the mRNA of HepG2 cells and the gene was then cloned into the pGEM-T vector. After being sequenced and analyzed with Vector NTI 9.1 and NCBI BLAST software, the target gene of PS1TP5 was cut from the pGEM-T vector and cloned into a yeast expression plasmid pGBKT7, then "bait" plasmid pGBKT7-PS1TP5 was transformed into the yeast strain AH109. The yeast protein was isolated and analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting hybridization. After expression of the pGBKT7-PS1TP5 fusion protein in the AH109 yeast strain was accomplished, a yeast two-hybrid screening was performed by mating AH109 with Y187 containing a leukocyte cDNA library plasmid. The mated yeast was plated on quadruple dropout medium and assayed for alpha-gal activity. The interaction between the PS1TP5 protein and the proteins obtained from positive colonies was further confirmed by repeating the yeast two-hybrid screen. After extracting and sequencing of plasmids from blue colonies we carried out a bioinformatic analysis.</p><p><b>RESULTS</b>Forty true positive colonies were selected and sequenced, full length sequences were obtained and we searched for homologous DNA sequences from GenBank. Among the 40 positive colonies, 23 coding genes with known functions were obtained, including Homo sapien leukocyte adhesion protein p150, 95, interleukin 2 receptor gamma chain, PALM2-AKAP2 protein (PALM2-AKAP2), eukaryotic translation initiation factor 4A, beta-2-microglobin, solute carrier family 9 (sodium/hydrogen exchanger), calreticulin, asialoglycoprotein receptor 1 (ASGR1), MHC class II lymphocyte antigen, cytochrome c oxidase subunit 1, lymphocyte antigen 86 (LY86) and lymphocyte cytosolic protein 1. One novel gene with unknown function was found and named as PS1TP5BP1. After being electronically spliced, it was deposited in GenBank (accession number: DQ471327).</p><p><b>CONCLUSIONS</b>Genes of proteins interacting with PS1TP5 were successfully screened from leukocyte cDNA library. These results suggested that PS1TP5 was closely correlated with immunoregulation, carbohydrate metabolism, signal transduction, the formation of hepatic fibrosis and initiation and development of tumors and also brought some new clues for further studying the biological functions of the pre-S1 protein.</p>

Screening and cloning target genes transactivated by hepatitis C virus F protein using suppression subtractive hybridization technique / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To identify and clone human genes transactivated by HCV F protein by constructing a cDNA subtractive library using the suppression subtractive hybridization technique.</p><p><b>METHODS</b>Suppression subtractive hybridization (SSH) and bioinformatics techniques were used for screening and cloning of the target genes transactivated by HCV F protein. The mRNA was isolated from HepG2 cells transfected with pcDNA3.1 (-)-F or with pcDNA3.1(-) empty vector as a control, and SSH method was employed to analyze the differentially expressed DNA sequence between the two groups. After restriction enzyme Rsa I digestion, small sized cDNAs were obtained. Then tester cDNA was divided into two groups and ligated to the specific adaptor 1 or adaptor 2. After tester cDNA was hybridized with driver cDNA twice and underwent two times of nested PCR, it was then subcloned into T/A plasmid vectors to set up the subtractive library. Amplification of the library was carried out with E. coli strain DH5 alpha. The cDNA was sequenced and analyzed in GenBank with blast search after PCR.</p><p><b>RESULTS</b>The subtractive library of genes transactivated by HCV F protein was constructed successfully. The amplified library contains 71 positive clones. Colony PCR shows that 56 clones contain 200-1000 bp inserts. Sequence analysis was performed on 28 clones randomly, and the full length sequences were obtained with using the bioinformatics method. Altogether 19 coding sequences were obtained, consisting of 17 known and 2 unknown.</p><p><b>CONCLUSIONS</b>The obtained sequences may be target genes transactivated by HCV F protein, and some gene coding proteins are those involved in cell cycle regulation, metabolism, and cell apoptosis.</p>

Effect of Endotoxin on the expression of peroxisome proliferator-activated receptor alpha in the development of nonalcoholic steatohepatitis in rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effect of endotoxin on the expression of peroxisome proliferator-activated receptor alpha (PPARa) in the development of nonalcoholic steatohepatitis in rats.</p><p><b>METHODS</b>A model of nonalcoholic steatohepatitis (NASH) was developed with Wistar rats fed a chow containing 20% maize oil for 14 weeks. The endotoxin group rats were intraperitoneally injected with lipopolysaccharide (LPS, 1 g/L, 3.0 ml/kg) once 4 hours before the end of the experiment. The concentrations of lipids, endotoxin, tumor necrosis factor-a, malondialdehyde, free fatty acid in plasma and hepatic tissues were determined and the degree of hepatocytic steatosis was studied. The expression of PPARa mRNA in hepatic tissues was measured using reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The expression of PPARa mRNA in the hepatic tissue of the LPS group was downregulated markedly in comparison to that of the control group. The level of free fatty acid and endotoxin by secreting tumor necrosis factor-a increased and triglyceride accumulated in the liver caused malondialdehyde content to increase, then lipid peroxidation process enhanced and ALT activity increased. Thus, hepatic injury and inflammatory reaction could be accelerated.</p><p><b>CONCLUSION</b>Endotoxemia can enhance hepatocellular steatosis and lead to NASH due to its downregulating the expression of PPARa mRNA.</p>