Co-administration of obeticholic acid and simvastatin protects against high-fat diet-induced non-alcoholic steatohepatitis in mice.

Non-alcoholic steatohepatitis (NASH) has no approved therapy. The farnesoid X nuclear receptor (FXR) agonist obeticholic acid (OCA) has shown promise as a drug for NASH, but can adversely affect plasma lipid profiles. Therefore, the present study aimed to investigate the effects and underlying mechanisms of OCA in combination with simvastatin (SIM) in a high-fat diet (HFD)-induced model of NASH. C57BL/6J mice were fed with a HFD for 16 weeks to establish the NASH model. The mice were randomly divided into the following five groups: HFD, HFD + OCA, HFD + SIM, HFD + OCA + SIM and control. After 16 weeks, the mice were sacrificed under anesthesia. The ratios of liver weight to body weight (Lw/Bw) and of abdominal adipose tissue weight to body weight were calculated. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol, triglycerides and low-density lipoprotein were measured. Liver sections were stained with hematoxylin and eosin. The protein levels of FXR, small heterodimeric partner (SHP) and cytochrome P450 family 7 subfamily A member 1 (CYP7A1) in the liver were detected by western blotting, while the mRNA levels of FXR, SHP, CYP7A1, bile salt export pump, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), sterol regulatory element binding protein-1 (SREBP1) and fatty acid synthase (FASN) were examined by reverse transcription-quantitative polymerase chain reaction. The administration of OCA with or without SIM reduced the liver inflammation score compared with those of the HFD and HFD + SIM groups, with no significant difference between the HFD + OCA and HFD + OCA + SIM groups. The steatosis score followed similar trends to the inflammation score. In HFD-fed mice, OCA combined with SIM prevented body weight gain compared with that in HFD and HFD + OCA groups, and reduced the Lw/Bw ratio compared with that in the HFD and HFD + SIM groups. In addition to preventing HFD-induced increases of ALT and AST, the combination of OCA and SIM reduced the mRNA levels of IL-6, TNF-α, SREBP1 and FASN. On the basis of these results, it may be concluded that the strategy of combining OCA with SIM represents an effective pharmacotherapy for NASH.

CD14+ monocytes and CD163+ macrophages correlate with the severity of liver fibrosis in patients with chronic hepatitis C.

Hepatic fibrosis is a crucial pathological process involved in the development of chronic hepatitis C (CHC) and may progress to liver cirrhosis and hepatocellular carcinoma. Activated peripheral blood monocytes and intrahepatic macrophages further promote hepatic fibrogenesis by releasing proinflammatory and profibrogenic cytokines. The present study aimed to investigate the role of peripheral CD14+ monocytes and intrahepatic CD163+ macrophages in hepatitis C virus (HCV)-associated liver fibrosis and clarify whether serum soluble CD163 (sCD163) may serve as a fibrosis marker in patients with CHC. A total of 87 patients with CHC and 20 healthy controls were recruited. Serum sCD163 levels were measured by ELISA. Frequencies of peripheral CD14+ monocytes and inflammatory cytokines expressed by CD14+ monocytes were analyzed by flow cytometry. The degree of fibrosis in human liver biopsies was graded using the Metavir scoring system and patients were stratified into two groups based on those results (F<2 vs. F≥2). Hepatic expression of CD163 was examined by immunohistochemical staining. The diagnostic values of sCD163, aspartate aminotransferase to platelet ratio index (APRI), fibrosis 4 score (FIB-4) and the aspartate aminotransferase to alanine aminotransferase ratio (AAR) in significant fibrosis (F≥2) were evaluated and compared using receiver operating characteristic (ROC) curves. The results indicated that the serum sCD163 levels and the frequency of CD14+ monocytes were significantly higher in the patients than that in the controls and positively correlated with liver fibrosis. The level of serum sCD163 was consistent with hepatic CD163 expression in the liver sections from patients. The frequencies of interleukin (IL)-8- and tumor necrosis factor-α-expressing monocytes were increased and that of IL-10-expressing monocytes was decreased in the patients. The area under the ROC curve (AUROC) for sCD163, APRI, FIB-4 and AAR was 0.876, 0.785, 0.825 and 0.488, respectively, and the AUROC for sCD163 was significantly higher than those for APRI and AAR. In conclusion, sCD163 may serve as a novel marker for assessing the degree of liver fibrosis in HCV-infected patients.

Emperipolesis mediated by CD8+ T cells correlates with biliary epithelia cell injury in primary biliary cholangitis.

Primary biliary cholangitis (PBC) is an autoimmune disease characterized by chronic destruction of the bile ducts. A major unanswered question regarding the pathogenesis of PBC is the precise mechanisms of small bile duct injury. Emperipolesis is one of cell-in-cell structures that is a potential histological hallmark associated with chronic hepatitis B. This study aimed to clarify the pathogenesis and characteristics of emperipolesis in PBC liver injury. Sixty-six PBC patients, diagnosed by liver biopsy combined with laboratory test, were divided into early-stage PBC (stages I and II, n = 39) and late-stage PBC (stages III and IV, n = 27). Emperipolesis was measured in liver sections stained with haematoxylin-eosin. The expressions of CK19, CD3, CD4, CD8, CD20, Ki67 and apoptosis of BECs were evaluated by immunohistochemistry or immunofluorescence double labelling. Emperipolesis was observed in 62.1% of patients with PBC, and BECs were predominantly host cells. The number of infiltrating CD3+ and CD8+ T cells correlated with the advancement of emperipolesis (R2  = 0.318, P < .001; R2  = 0.060, P < .05). The cell numbers of TUNEL-positive BECs and double staining for CK19 and Ki67 showed a significant positive correlation with emperipolesis degree (R2  = 0.236, P < .001; R2  = 0.267, P < .001). We conclude that emperipolesis mediated by CD8+ T cells appears to be relevant to apoptosis of BEC and thus may aggravate the further injury of interlobular bile ducts.

LncRNA-ATB/microRNA-200a/ß-catenin regulatory axis involved in the progression of HCV-related hepatic fibrosis.

OBJECTIVE(S): Long noncoding RNAs (lncRNAs)-activated by transforming growth factor beta (lncRNA-ATB) is known to be involved in the invasion of hepatocellular carcinoma by regulating target genes of miR-200a. However, the role and molecular mechanisms of lncRNA-ATB/miR-200a in HCV-related liver fibrosis remains unclear. In this study, we examined the expression of lncRNA-ATB/miR-200a, and their target gene ß-Catenin in liver tissues of HCV patients and hepatic stellate cells (HSCs) to elucidate the possible role of lncRNA-ATB/miR-200a axis in HSC activation and development of liver fibrosis. MATERIALS AND METHODS: Liver tissues were obtained by biopsy or surgery from eighteen HCV patients with severe liver fibrosis and six healthy subjects (control). Conditioned media (CM) from cultured HepG2-CORE cells (HepG2 cells stably expressing HCV core protein) were used to treat LX-2 cells. The binding sites between lncRNA-ATB/miR-200a and ß-catenin were predicted and then verified by a dual luciferase reporter assay. The effect of lncRNA-ATB/miR-200a/ß-catenin on HSC activation was assessed by examining the expression of alpha-smooth muscle actin (α-SMA) and collagen type 1 alpha 1 (Col1A1) in HSCs. Further, the regulatory role of lncRNA-ATB on HSC activation and miR-200a/ß-catenin expression was assessed by using siRNA-mediated knockdown of lncRNA-ATB. RESULTS: LncRNA-ATB was up-regulated in fibrotic liver tissues and activated LX-2 cells treated with CM from HepG2-CORE cells. Dual luciferase reporter assays confirmed that lncRNA-ATB contained common binding sites for miR-200a and ß-catenin. Decreased expression of miR-200a and increased expression of ß-catenin were observed in liver tissues of patients with HCV-related hepatic fibrosis and activated HSCs. Knockdown of lncRNA-ATB could down-regulate ß-catenin expression by up-regulating the endogenous miR-200a and suppress the activation of LX-2 cells. CONCLUSION: LncRNA-ATB/miR-200a/ß-catenin regulatory axis likely contributed to the development of liver fibrosis in HCV patients. Knockdown of lncRNA-ATB might be a novel therapeutic target for HCV-related liver fibrosis.

Tim-3 suppression combined with TLR3 activation enhances antiviral immune response in patients with chronic HCV infection.

OBJECTIVE: To investigate the regulation mechanism of T cell immunoglobulin and mucin domain-3 (Tim-3) combined with toll-like receptor 3 (TLR3) or TLR4 on antiviral immune and inflammatory response in patients with chronic hepatitis C virus (HCV) infection. METHODS: Patients with chronic HCV infection and healthy control subjects were recruited. Patients received interferon (IFN)-α based therapy. Plasma galectin-9 (Gal-9) was quantitated. Peripheral blood mononuclear cells (PBMCs) were cultured with TLR3 or TLR4 agonists, alone or in combination with Tim-3 antagonist. Levels of IFN-α, TNF-α, and 2'-5' oligoadenylate synthetase (2'-5'OAS), myxovirus resistance protein A (MxA) and suppressor of cytokine 1 (SOCS1) RNA in PBMC cultures were evaluated. RESULTS: Plasma Gal-9 levels were increased in patients (n = 52) compared with controls (n = 20) and significantly declined at treatment week 12 and 24 weeks post-treatment. IFN-α, 2'-5'OAS, MxA, TNF-α and SOCS1 were upregulated by TLR3 and TLR4 agonists. TNF-α and SOCS1 levels were suppressed by the addition of Tim-3 antagonist. CONCLUSIONS: Tim-3 blockade in combination with TLR activation induces the expression of antiviral molecules without a significant increase in TNF-α or SOCS1.

A Patient With Primary Biliary Cirrhosis Accompanied by Wilson's Disease.

INTRODUCTION: Both primary biliary cirrhosis (PBC) and Wilson's disease (WD) can cause copper retention in the liver, which is an important factor for liver cellular damage. Copper chelation may preserve liver cell function. It is challenging to distinguish WD from copper accumulation in patients with PBC. There have been few case reports of PBC co-occurrence with WD. CASE PRESENTATION: Here we report a case of PBC with WD in a 55-year-old Chinese male. In addition to the typical pathological characteristics of PBC and a large number of copper depositions in the liver, the patient showed WD ATP7B gene mutations. CONCLUSIONS: Co-occurrence of PBC with WD is rare, which can cause diffusely intrahepatic copper deposition. Early liver biopsy and genetic testing are necessary for the diagnosis. The combination of ursodeoxycholic acid with zinc and sodium dimercaptopropane sulfonate is effective.

Gamma-glutamyl transpeptidase to platelet ratio index is a good noninvasive biomarker for predicting liver fibrosis in Chinese chronic hepatitis B patients.

Objective To evaluate whether gamma-glutamyl transpeptidase to platelet ratio index (GPRI) can diagnose the extent of liver fibrosis in Chinese patients with chronic hepatitis B (CHB) infection. Methods This prospective observational study used liver biopsy results as the gold standard to evaluate the ability of GPRI to predict hepatic fibrosis compared with two other markers, the aspartate aminotransferase (AST) to platelet ratio index (APRI) and fibrosis-4 score (FIB-4). The clinical and demographic factors that affected GPRI, independent of liver fibrosis, were assessed using multivariate linear regression analyses. Results This study enrolled 312 patients with CHB. GPRI had a significantly positive correlation with liver fibrosis stage and the correlation coefficient was higher than that for APRI and FIB-4. The areas under the receiver operating curves for GPRI for significant fibrosis, bridging fibrosis, and cirrhosis were 0.728, 0.836, and 0.842, respectively. Of the three indices, GPRI had the highest diagnostic accuracy for bridging fibrosis and cirrhosis. Age, elevated AST and elevated total bilirubin levels were independent determinants of increased GPRI. Conclusion GPRI was a more reliable laboratory marker than APRI and FIB-4 for predicting the stage of liver fibrosis in Chinese patients with CHB.

Individualized treatment strategies and predictors of virological response for chronic hepatitis C: a multicenter prospective study from China.

Combination therapy comprising pegylated interferon-alpha (PegIFNα) and ribavirin (RBV) has been the standard of care for the chronic hepatitis C patients for more than a decade. Recently, direct antiviral agents show better efficacy, tolerance, and shorter treatment duration. However, the prohibitive costs of the regimens limit their use in developing countries where most of the HCV infection exists. Optimizing the treatment and understanding the host- and virus-factors associated with viral clearance were necessary for individualizing therapy to maximize sustained virologic response. To explore individualized antiviral strategies with PegIFNα-2a/IFNα-2b plus ribavirin for CHC patients, and to clarify predictive factors for virological response. A cohort of 314 patients were included in this open-label, prospective clinical trial, which received individualized doses of PegIFNα-2a or IFNα-2b combined with RBV according to body weight, disease status and complications, with the duration of 44 weeks after HCV RNA undetectable. All the IL-28B (rs8099917), IL-17A (rs8193036), IL-17B (rs2275913) and PD-1.1 SNPs were genotyped using the TaqMan system. The sustained virological response (SVR) in PegIFNα-2a group was significantly higher than that in IFNα-2b (85.8% vs 75.0%, P = 0.034), especially in HCV genotype 1 (84.0% vs 64.3%, P = 0.022). However, no significant differences were found in rapid virological response (RVR), complete early virological response (cEVR) and SVR between PegIFNα-2a and IFNα-2b according to different doses, respectively. The genotype frequency of IL-28B TT in patients with cEVR, SVR was higher than that in non-responsed patients (93.8% vs 78.1%, χ(2) = 7.827, P = 0.005; 95.9% vs 80.4%, χ(2) = 9.394, P = 0.002). No significant correlation between the genotype distribution of IL-17A, IL-17B and PD-1.1 with virological response. Individualized regimens of PegIFNα-2a/RBV and IFNα-2b/RBV could achieve satisfied virological response in Chinese HCV patients. The IL-28B (rs8099917) TT genotype is a clinical usefully marker for cEVR and SVR.

Dichlorvos induced autoimmune hepatitis: a case report and review of literature.

INTRODUCTION: Drug-induced liver injury is a frequent cause of hepatic dysfunction. Several drugs have been identified to cause autoimmune hepatitis (AIH). Environmental chemicals are capable of triggering a certain degree of liver injury. However, toxin induced AIH is rare. CASE PRESENTATION: We reported a woman with chronic (long-term) exposures to dichlorvos, which resulted in liver injury and cirrhosis. She was diagnosed after a second liver biopsy, which was correlated with laboratory findings. At the same time, she experienced hepatic cortical blindness during her first admission. CONCLUSIONS: Chronic (long-term) exposures to dichlorvos can lead to AIH. A detailed inquiry of medical history and liver biopsy are necessary for the diagnosis of toxin-induced AIH. Corticosteroid therapy is associated with favorable evolution.

Modulation of IKKß/NF-κB and TGF-ß1/Smad via Fuzheng Huayu recipe involves in prevention of nutritional steatohepatitis and fibrosis in mice.

OBJECTIVES: Fuzheng Huayu recipe (FZHY) exerts significant protective effects against liver fibrosis by strengthening the body's resistance and removing blood stasis. However, the molecular mechanisms through which FZHY affects liver fibrosis are still unclear. In this study, we examined the expression levels of factors involved in the inhibitor κB kinase-ß (IKK-ß)/nuclear factor-κB (NF-κB) and transforming growth factor beta 1 (TGF-ß1)/Smad signaling pathways to elucidate whether FZHY could attenuate nutritional steatohepatitis and fibrosis in mice. MATERIALS AND METHODS: C57BL/6J mice were fed with methionine-choline deficient (MCD) diet for 8 weeks to induce fibrotic steatohepatitis. FZHY and/or heme oxygenase-1 (HO-1) chemical inducer (hemin) were administered to mice. The effects of FZHY alone and in combination with hemin were assessed by comparing the severity of hepatic injury, activation of hepatic stellate cells (HSCs), and the expression of oxidative stress, inflammation and fibrogenesis related genes. RESULTS: Administration of FZHY, hemin and FZHY plus hemin significantly ameliorated liver injury. Additionally, our analysis indicated that administration of these agents significantly attenuated oxidative stress, downregulated the expression of pro-inflammatory and pro-fibrotic genes, including IKK-ß, NF-κB, monocyte chemoattractant protein-1 (MCP-1), α-smooth muscle actin (α-SMA), TGF-ß1, Smad3 and Smad4, and upregulated the expression of the antifibrogenic gene Smad7 (P< 0.001). CONCLUSION: FZHY-containing therapies prevented nutritional steatohepatitis and fibrosis through modulating the expression of factors associated with the IKKß/NF-κB and TGF-ß1/Smad signaling pathways and oxidative stress related genes.

Peroxisome proliferator-activated receptor α, a potential therapeutic target for alcoholic liver disease.

Alcoholic liver injury represents a progressive process with a range of consequences including hepatic steatosis, steatohepatitis, liver fibrosis, cirrhosis, and hepatocellular carcinoma. Targeting key molecular regulators involved in the development of alcoholic liver injury may be of great value in the prevention of liver injury. Peroxisome proliferator-activated receptor α (PPARα) plays a pivotal role in modulation of hepatic lipid metabolism, oxidative stress, inflammatory response and fibrogenesis. As such, PPARα may be a potential therapeutic target for the treatment of alcoholic liver disease.

Regulatory phenotype, PD-1 and TLR3 expression in T cells and monocytes from HCV patients undergoing antiviral therapy: a randomized clinical trial.

BACKGROUND & AIMS: The cellular immunity has a profound impact on the status of hepatitis C virus (HCV) infection. However, the response of cellular immunity on the virological response in patients with antiviral treatment remains largely unclear. We aimed to clarify the response of peripheral T cells and monocytes in chronic hepatitis C patients with antiviral treatment. METHODS: Patients with chronic hepatitis C were treated either with interferon alpha-2b plus ribavirin (n = 37) or with pegylated interferon alpha-2a plus ribavirin (n = 33) for up to 24 weeks. Frequencies of peripheral regulatory T-cells (Tregs), programmed death-1 (PD-1) expressing CD4+ T-cells or CD8+ T-cells and toll-like receptor (TLR) 3 expressing CD14+ monocytes were evaluated by flow cytometry in patients at baseline, 12 and 24 weeks following treatment and in 20 healthy controls. RESULTS: Frequencies of Tregs, PD-1 and TLR3 expressing cells were higher in patients than those in control subjects (P<0.05). Patients with complete early virological response (cEVR) showed lower Tregs, PD-1 expressing CD4+ or CD8+ T-cells than those without cEVR at 12 weeks (P<0.05). Patients with low TLR3 expressing CD14+ monocytes at baseline had a high rate of cEVR (P<0.05). CONCLUSIONS: Low peripheral TLR3 expressing CD14+ monocytes at baseline could serve as a predictor for cEVR of antiviral therapy in chronic HCV-infected patients. The cEVR rates were significantly increased in the patients with reduced circulating Tregs, PD-1 expressing CD4+ or CD8+ T-cells. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR10001090.

[Activation of Fas/FasL and its downstream signaling pathway promotes development of alcoholic steatohepatitis and liver fibrosis in mice].

OBJECTIVE: To explore the role and mechanism of the Fas/Fas ligand (FasL) system and its downstream signaling pathway related to the progression of alcoholic steatohepatitis and liver fibrosis. METHODS: Eighteen C57BL/6J mice were randomly divided into three groups: controls; alcoholic steatohepatitis model, given four-weeks of a 4% ethanol-containing Lieber-DeCarli liquid diet; alcoholic steatohepatitis and liver fibrosis model, given the four-week alcohol diet followed by twice weekly intraperitoneal injections of carbon tetrachloride (5% olive oil solution; 2 mL/kg dose) during the fifth to eighth weeks. Mice in the model groups were sacrificed at the end of week 4 and 8, respectively, along with control mice for comparative analyses. Liver tissue sections were evaluated for hepatocellular apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. The mRNA expression of Fas, FasL, cysteine aspartate-specific proteases 3 (caspase 3), and cytochrome P450 2E1 (CYP 2E1) in liver tissues was detected by reverse transcription (RT)-PCR, visualized by ethidium bromide staining, and normalized to the gray-value of GAPDH expression. The protein expression of Fas and caspase 3 were detected by western blotting (b-actin normalized), and of FasL and CYP 2E1 by immunohistochemistry staining. Intergroup differences and statistical significance were evaluated by single factor analysis of variance and the least squares difference-t test or the Kruskal-Wallis H test and the Mann-Whitney U test. RESULTS: The number of apoptotic cells in the liver sections was significantly higher in both model groups with alcoholic steatohepatitis (vs. controls) and the amount in the alcoholic steatohepatitis plus liver fibrosis model was significantly higher than that in the model with only alcoholic steatohepatitis. In addition, activation of Fas, FasL and its downstream signaling pathway showed an increasing trend with extent of liver injury. The hepatic mRNA (by RT-PCR) and protein (by western blotting) normalized expression levels in the controls, alcoholic steatohepatitis models, and alcoholic steatohepatitis plus liver fibrosis models were, respectively: Fas mRNA: 0.50+/-0.05, 0.61+/-0.10, 0.76+/-0.03 (H=12.137, P less than 0.05), protein: 0.52+/-0.14, 0.86+/-0.10, 0.99+/-0.09 (F=12.758, P less than 0.01); FasL mRNA: 0.31+/-0.03, 0.53+/-0.02, 1.02+/-0.04 (F=153.260, P less than 0.01); caspase 3 mRNA: 0.86+/-0.11, 0.85+/-0.05, 1.33+/-0.16 (F=8.740, P less than 0.01), protein: 0.40+/-0.03, 0.69+/-0.06, 1.02+/-0.10 (F=90.785, P less than 0.01); CYP 2E1 mRNA: 0.72+/-0.14, 1.00+/-0.15, 1.30+/-0.20 (H=4.713, P less than 0.01). The changes in hepatic FasL and CYP 2E1 expression detected by immunohistochemistry were consistent with the mRNA expression. CONCLUSION: Activation of Fas/FasL and its downstream signaling pathway, which induces hepatocellular apoptosis, contributes to the development of alcoholic steatohepatitis and liver fibrosis.

Activation of peroxisome proliferator activated receptor alpha ameliorates ethanol mediated liver fibrosis in mice.

BACKGROUND: Peroxisome proliferator activated receptor alpha (PPARα) ameliorates ethanol induced hepatic steatohepatitis. However, its role in alcoholic liver fibrosis has not been fully clarified. The aim of this study was to elucidate the effect and the molecular basis of PPARα in ethanol induced liver fibrosis in mice. METHODS: C57BL/6J mice were fed with 4% ethanol-containing Lieber-DeCarli liquid diet for eight weeks, and intraperitoneal injected with 5% carbon tetrachloride (CCl4) for the last four weeks to induce alcoholic liver fibrosis. PPARα agonist WY14643 was administered to mice during the last couple of weeks. The effects of PPARα induction on liver histology, activation of hepatic stellate cells (HSCs), as well as hepatic expression of inflammatory and fibrogenic factors were assessed. RESULTS: The ethanol plus CCl4 treated mice exhibited progressive liver injury including piecemeal necrosis of hepatocytes, severe inflammatory cells infiltration and bridging fibrosis. This was accompanied by down-regulated hepatic expression of PPARα and the protective cytokines adiponectin, heme oxygenase-1 and interleukin-10. Additionally, up-regulation of the proinflammatory cytokine tumor necrosis factor-alpha, as well as the profibrogenic genes osteopontin, transforming growth factor-beta 1, visfatin, phosphatidylinositol 3-kinase, matrix metalloproteinase-2 (MMP-2) and MMP-9 was observed. WY14643 treatment restored expression of cytokines altered by ethanol plus CCl4 treatment and concomitantly ameliorated the liver injury. CONCLUSIONS: The present study provides evidence for the protective role of PPARα induction in ameliorating ethanol mediated fibrosis through mediation of inflammatory and fibrogenic factors.

Fuzheng Huayu recipe prevents nutritional fibrosing steatohepatitis in mice.

BACKGROUND: Fuzheng Huayu recipe (FZHY), a compound of Chinese herbal medicine, was reported to improve liver function and fibrosis in patients with hepatitis B virus infection. However, its effect on nutritional fibrosing steatohepatitis is unclear. We aimed to elucidate the role and molecular mechanism of FZHY on this disorder in mice. METHODS: C57BL/6 J mice were fed with methionine-choline deficient (MCD) diet for 8 weeks to induce fibrosing steatohepatitis. FZHY and/or heme oxygenase-1 (HO-1) chemical inducer (hemin) were administered to mice, respectively. The effect of FZHY was assessed by comparing the severity of hepatic injury, levels of hepatic lipid peroxides, activation of hepatic stellate cells (HSCs) and the expression of oxidative stress, inflammatory and fibrogenic related genes. RESULTS: Mice fed with MCD diet for 8 weeks showed severe hepatic injury including hepatic steatosis, necro-inflammation and fibrosis. Administration of FZHY or hemin significantly lowered serum levels of alanine aminotransferase, aspartate aminotransferase, reduced hepatic oxidative stress and ameliorated hepatic inflammation and fibrosis. An additive effect was observed in mice fed MCD supplemented with FZHY or/and hemin. These effects were associated with down-regulation of pro-oxidative stress gene cytochrome P450 2E1, up-regulation of anti-oxidative gene HO-1; suppression of pro-inflammation genes tumor necrosis factor alpha and interleukin-6; and inhibition of pro-fibrotic genes including α-smooth muscle actin, transforming growth factor beta 1, collagen type I (Col-1) and Col-3. CONCLUSIONS: Our study demonstrated the protective role of FZHY in ameliorating nutritional fibrosing steatohepatitis. The effect was mediated through regulating key genes related to oxidative stress, inflammation and fibrogenesis.

[Peroxisome proliferator activated receptor gamma activation and overexpression prevent hepatocellular apoptosis of nutritional fibrotic steatohepatitis in mice].

OBJECTIVE: To elucidate the effect of targeted gene modulation of peroxisome proliferator activated receptor gamma (PPARg) on hepatocellular apoptosis in nutritional fibrotic steatohepatitis in mice. C57BL/6J mice were fed with high fat, methionine-choline deficient (MCD) diet for 8 weeks to induce fibrotic steatohepatitis. Mice fed the MCD diet were treated with adenovirus carrying PPARg (Ad-PPARg), adenovirus-beta-galactosidase (Ad-LacZ), Ad-PPARg plus PPARg agonist rosiglitazone, or PPARg antagonist 2-chloro-5-nitro- benzanilide (GW9662), respectively. H and E stain was performed for observation of hepatocellular apoptosis, hepatic steatosis, inflammation and fibrosis in the liver sections. The expression levels of mRNA and protein of PPARg and apoptosis related genes, Fas, Fas Ligand (FasL), B cell lymphoma/leukemia-2 (Bcl-2), Bcl-2 associated X protein (Bax) and cysteine-containing aspartate-specific proteases-3 (caspase-3) were detected by real-time RT-PCR and Western blot assay, respectively. RESULTS: Mice fed with MCD diet for 8 weeks showed severe hepatic injury including steatosis, hepatocellular apoptosis, inflammatory infiltration and fibrosis, concomitancy with enhanced expression of pro-apoptosis genes, Fas, FasL, Bax and caspase-3 and increased expression of anti-apoptosis gene Bcl-2, by comparing with the control group. The mRNA expression levels of these genes were 3.59+/-0.35 vs 1.11+/-0.37, 4.37+/-1.03 vs 1.09+/-0.33, 4.27+/-0.48 vs 1.03+/-0.10, 4.93+/-0.67 vs 1.12+/-0.24 and 3.95+/-0.34 vs 1.20+/-0.19, and LSD-t values were 2.49, 3.28, 3.25, 3.80 and 2.75, as compared with the control group, P is less than 0.01; the protein expression levels were 1.96+/-0.07 vs 0.45+/-0.07, 0.53+/-0.07 vs 0.22+/-0.02, 1.32+/-0.06 vs 0.59+/-0.03, 1.51+/-0.23 vs 0.36+/-0.09 and 0.57+/-0.01 vs 0.29+/-0.01, and LSD-t values were 1.51, 0.31, 0.73, 1.14 and 0.28, P is less than 0.01. Administration of PPARg agonist rosiglitazone and/or Ad-PPARg significantly ameliorated hepatic steatosis, hepatocellular apoptosis, necro inflammation and fibrosis. These effects were associated with repressed expression of pro-apoptosis genes and up-regulated expression of anti-apoptosis gene. After rosiglitazone treatment, the mRNA expression levels were 3.78+/-0.58, 3.66+/-0.83, 3.04+/-0.37, 2.54+/-0.62 and 4.42+/-0.42, and LSD-t values were 0.18, 0.71, 1.23, 2.39 and 0.46, as compared with MCD group, the P values were 0.627, 0.241, less than 0.01, less than 0.01 and 0.278, the protein expression levels were 1.06+/-0.03, 0.30+/-0.01, 0.70+/-0.05, 1.19+/-0.30 and 0.90+/-0.01, and LSD-t values were 0.90, 0.23, 0.62, 0.31 and 0.34, the P values were less than 0.01, less than 0.01, less than 0.01, 0.122, less than 0.01. After Ad-PPARg treatment, the mRNA expression levels were 2.31+/-0.16, 2.71+/-0.23, 2.52+/-0.27, 1.79+/-0.32 and 5.97+/-0.72, and LSD-t values were 1.28, 1.66, 1.75, 3.13 and 2.02, as compared with MCD group, P is less than 0.05; the protein expression levels were 1.73+/-0.07, 0.43+/-0.04, 1.01+/-0.08, 1.31+/-0.10 and 1.56+/-0.04, and LSD-t values were 0.23, 0.10, 0.30, 0.20 and 0.99, with P values equal 0.009, 0.01, less than 0.01, 0.322 and less than 0.01. CONCLUSIONS: This study provided evidences for the protective role of activation and overexpression of PPARg in ameliorating hepatocellular apoptosis in mice with hepatic fibrosing steatohepatitis.

[The role of Fas mutation on non-alcoholic steatohepatitis in mice].

OBJECTIVE: Our previous study indicated that the death receptor Fas played a key role on hepatocyte apoptosis in nutritional steatohepatitis in mice. This study aimed to explore whether Fas mutation accelerated hepatic steatosis and inflammatory infiltration in methionine-choline deficient (MCD) diet feeding mice. METHODS: Mice homozygous for the lymphoproliferation spontaneous mutation (C57BL/6J-Faslpr) and wild type C57BL/6J mice were fed with MCD diet for three weeks to induce non-alcoholic steatohepatitis (NASH). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG) and total cholesterol (TC) levels were detected by an Olympus AU5400 automatic chemical analyzer. The role of Fas gene mutation on NASH was assessed by comparing the severity of hepatic steatosis and inflammation in the liver sections, the mRNA and protein expressions of hepatic inflammatory and fibrogenesis related factors, proliferating cell nuclear antigen (PCNA) and transforming growth factor beta 1 (TGFb1). RESULTS: The serum ALT levels of the wild type and Faslpr mice fed with MCD were significant higher than that of the control mice (126.33+/-10.50 U/L vs (25.00+/-10.14) U/L, (160.33+/-48.29) U/L vs (18.33+/-9.08) U/L, with the LSD-t value 12.02, 5.08 respectively, the P value<0.001, 0.007 respectively. The serum ALT levels showed no significant difference between the Faslpr and wild type mice fed with MCD, with the LSD-t value 1.19, the P value 0.229. The serum AST, TG and TC levels showed neithere significant difference among the four groups. MCD diet induced hepatic steatosis and inflammatory infiltration in both of the wild type and Faslpr mice. Especially, severer hepatic injury was observed in Faslpr mice as compared with wild type mice. The mRNA expression levels of cell proliferation factor PCNA and fibrogenesis growth factor TGF b1 in wild type mice fed with MCD were significantly higher than that of the control mice (2.84+/-0.73, 2.77+/-0.54 vs 1.31+/-0.18, 0.89+/-0.18), with the LSD-t value 4.99, 8.08 respectively, the P value 0.001, <0.001 respectively. The mRNA expression levels of PCNA and TGFb1 in Faslpr mice fed with MCD were significantly higher than that of the Faslpr control mice and the wild type mice fed with MCD (5.57+/-1.13, 5.73+/-0.89 vs 1.04+/-0.16, 0.85+/-0.11 and 2.84+/-0.73, 2.77+/-0.54), with the LSD-t value 10.15, 13.19 and 5.33, 6.91 respectively, the P value<0.001. The protein expressions levels of PCNA and TGFb1 were concordant with the mRNA. CONCLUSIONS: Faslpr promoted hepatic steatosis and inflammatory infiltration in mice fed with MCD diet, which might associated with excessive release of cell proliferative, inflammatory and fibrogenesis factors.

Induction of heme oxygenase-1 protects against nutritional fibrosing steatohepatitis in mice.

BACKGROUND: Heme oxygenase-1 (HO-1), an antioxidant defense enzyme, has been shown to protect against oxidant-induced liver injury. However, its role on liver fibrosis remains unclear. This study aims to elucidate the effect and the mechanism of HO-1 in nutritional fibrosing steatohepatitis in mice. METHODS: Male C57BL/6J mice were fed with a methionine-choline deficient (MCD) diet for eight weeks to induce hepatic fibrosis. HO-1 chemical inducer (hemin), HO-1 chemical inhibitor zinc protoporphyrin IX (ZnPP-IX) and/or adenovirus carrying HO-1 gene (Ad-HO-1) were administered to mice, respectively. Liver injury was assessed by serum ALT, AST levels and histological examination; hepatic lipid peroxides levels were determined; the expression levels of several fibrogenic related genes were assayed by real-time quantitative PCR and Western blot. RESULTS: MCD feeding mice showed progressive hepatic injury including hepatic steatosis, inflammatory infiltration and fibrosis. Induction of HO-1 by hemin or Ad-HO-1 significantly attenuated the severity of liver injury. This effect was associated with the up-regulation of HO-1, reduction of hepatic lipid peroxides levels, down-regulation of inflammatory factors tumor necrosis factor-alpha, interleukin-6 and suppressor of cytokine signaling-1 as well as the pro-fibrotic genes alpha-smooth muscle actin, transforming growth factor-ß1, matrix metallopeptidase-2 and matrix metallopeptidase-9. A contrary effect was observed in mice treated with ZnPP-IX. CONCLUSIONS: The present study provided the evidence for the protective role of HO-1 in ameliorating MCD diet-induced fibrosing steatohepatitis. Modulation of HO-1 expression might serve as a therapeutic approach for fibrotic steatohepatitis.

Adenovirus-mediated peroxisome proliferator activated receptor gamma overexpression prevents nutritional fibrotic steatohepatitis in mice.

OBJECTIVE: The pathogenesis of non-alcoholic steatohepatitis is still unclear. We have demonstrated previously that peroxisome proliferator activated receptor gamma (PPARγ) ligand protects against inflammation and fibrogenesis in experimental non-alcoholic steatohepatitis. We aim to elucidate the effect and the mechanism of PPARγ itself on nutritional fibrotic steatohepatitis in mice. METHODS: C57BL/6J mice were fed with methionine-choline deficient (MCD) diet for 8 weeks to induce fibrotic steatohepatitis. Mice fed the MCD diet were treated with adenovirus carrying PPARγ (Ad-PPARγ), Ad-PPARγ plus PPARγ agonist rosiglitazone, or PPARγ antagonist 2-chloro-5-nitrobenzaniliden (GW9662), respectively. The effects of up-regulation of PPARγ in the presence or absence of its agonist/or antagonist were assessed by comparing the severity of hepatic injury, activation of hepatic stellate cells and the expression of adiponectin, heme oxygenase-1, and fibrogenic related genes. RESULTS: Mice fed with MCD diet for 8 weeks showed severe hepatic injury including hepatic steatosis, inflammatory infiltration, and fibrosis. Administration of Ad-PPARγ significantly lowered serum alanine aminotransferase level and ameliorated hepatic steatosis, necroinflammation, and fibrosis. These effects were associated with enhanced expression of PPARγ, up-regulated expression of adiponectin and heme oxygenase-1, and down-regulated expression of tumor necrosis factor alpha, interleukin-6, α-smooth muscle actin, transforming growth factor beta 1, matrix metallopeptidase-2, and -9. Administration of GW9662 promoted the severity of liver histology. CONCLUSIONS: The present study provided evidences for the protective role of overexpressing PPARγ in ameliorating hepatic fibrosing steatohepatitis in mice. Modulation of PPARγ expression might serve as a therapeutic approach for fibrotic steatohepatitis.

[The role of heme oxygenase-1 in non-alcoholic steatohepatitis].

OBJECTIVE: To investigate the potential role of heme oxygenase-1 on preventing non-alcoholic steatohepatitis (NASH) in mice. METHODS: Experimental models of NASH were established by feeding male C57BL/6J mice with choline-methionine deficient diet (MCD) for four weeks. Control animals were fed with choline-methionine supplemented diet. The treatment groups were fed with MCD diet combined with HO-1 inducer hemin or inhibitor zinc protoporphyrin IX (ZnPP-IX). Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were tested by enzymic method with automatic biochemistry analyzer. The degree of hepatic steatosis, inflammation and fibrosis were examined under HE staining. The hepatic mRNA and protein expressions of HO-1, TNFalpha and IL-6 were analyzed by RT-PCR and Western blot respectively. MCD fed mice showed increased serum ALT and AST levels and moderate to severe hepatic steatosis with inflammatory infiltration, hepatic spot or focal necrosis, light portal and sinus hepaticus fibrosis in the liver sections, which associated with enhanced expression of HO-1, TNFalpha and IL-6 mRNA and protein (1.13+/-0.11, 1.74+/-0.05; 0.20+/-0.01, 1.92+/-0.10; 0.58+/-0.02, 2.06+/-0.05 vs 0.43+/-0.02, 0.75+/-0.05; 0.08+/-0.00, 0.59+/-0.02; 0.22+/-0.01, 0.91+/-0.02). Administration of hemin significantly decreased serum ALT and AST levels and attenuated hepatic steatosis and necroinflammation which associated with up-regulation of antioxidative gene HO-1 and down-regulation of pro-inflammatory cytokines TNFalpha and IL-6 (P < 0.01). A contrary effect on serum aminotransferase levels and liver histopathology was observed in mice injected with ZnPP-IX (P < 0.01). CONCLUSIONS: The effect was associated with suppressed HO-1 expression and increased TNFaLPHA and IL-6 expression. The data provided a biochemical, morphological and molecular biological evidence for the protective role of HO-1 in ameliorating hepatic steatosis, necroinflammation in experimental nutritional steatohepatitis.