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Inflammatory activation of hepatic macrophages plays a primary role in drug-induced liver injury (DILI). However, the exact mechanism underlying DILI remains unclear.A total of 328 DILI patients and 80 healthy individuals were prospectively enrolled in this study. The DILI patients were categorized into subgroups based on either disease severity or histopathological patterns. Plasma soluble CD163 (sCD163) and hepatic CD163 were examined to determine hepatic macrophage activation, and CD8, CD20, and MUM-1 were assessed to determine cellular immunity using immunohistochemistry. The lipopolysaccharide (LPS) pathway proteins [e.g. LPS, soluble CD14 (sCD14), and LPS-binding protein (LBP)] were measured using enzyme-linked immunosorbent assay.Plasma sCD163 levels were nine-fold higher in DILI patients than in healthy controls at the baseline, but significantly decreased at the 4-week follow-up visit after treatment. The numbers of hepatic macrophages, B cells, and plasma cells were significantly higher in the liver tissues from DILI patients than those from healthy controls. Furthermore, the baseline levels of LPS pathway proteins in the DILI patients were significantly higher than those in the controls. Notably, these proteins significantly decreased at the 4-week follow-up visit but remained significantly higher than the levels for the controls.Hepatic inflammation in DILI involves the activation of hepatic macrophages and cellular immunity, in which the LPS pathway likely plays a role, at least in part. As such, this study has improved our understanding of the pathological mechanisms for DILI and may facilitate the development of better treatments for patients with DILI.

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 (R 2 = 0.318, P

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.

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.

To determine the role of IGF-1/PI3K pathway and investigate the molecular mechanism of Fuzhenghuayu (FZHY) therapy in a spontaneous recovery rat model of liver fibrosis.The liver fibrosis model was induced in male Wistar rats by administering 8 weeks of twice weekly CCL4 intraperitoneal injections without (untreated model) or with once daily FZHY (treated model). Normal, untreated rats served as the control group. At weeks 4, 6 and 8 (fibrosis) and 10, 12 and 14 (spontaneous recovery) after modeling initiation, effects on protein (a-SMA, IGF-1, PI3K) and mRNA (IGF-1, PI3K) expression levels were evaluated by immunohistochemistry and RT-PCR, respectively. Serum markers of liver function (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and liver cell damage (alkaline hydrolysis, HYP) were measured. Histology was performed to assess the degree of inflammation and fibrosis (Ishak scoring system).In the untreated model group, progression of liver fibrosis (weeks 4, 6 and 8) was accompanied by gradual increases in inflammation, necrosis, serum ALT and AST, and hepatic expression of a-SMA protein and IGF-1 and PI3K protein and mRNA; however, during the spontaneous recovery period (weeks 10, 12 and 14) the IGF-1 and PI3K protein and mRNA levels rapidly decreased and the HYP level, Ishak score, and a-SMA hepatic expression also decreased. The FZHY-treated model group showed significantly lower fibrosis-related up-regulation of IGF-1 and PI3K protein and mRNA expression, HYP level, Ishak score, and a-SMA hepatic expression at each time point (vs. untreated model group).The IGF-1/PI3K pathway may contribute to progression of liver fibrosis. The mechanism by which FZHY prevents liver fibrosis in a rat model may involve blocking of the IGF/PI3K pathway and inhibiting HSC activation.

To investigate the association of single nucleotide polymorphisms (SNPs) in the interleukin 17 (IL-17) gene and serum protein levels in patients with chronic hepatitis C virus (HCV) infection.A total of 228 patients with chronic HCV infection and 81 healthy controls were enrolled in the study. The frequencies of IL-17 rs8193036 and rs2275913 polymorphisms were detected by the TaqMan SNP genotyping assay. Serum levels of IL-17 protein were detected by ELISA. Pairwise comparisons were made by the Chi-square test, and the significance of between-group differences was assessed by the Student's t-test with P less than 0.05.The patients with chronic HCV infection and the healthy controls showed similar frequencies of the rs8193036 C/T allele (x2 = 1.428, P = 0.232) and the rs2275913 A/G allele (x2 = 0.106, P = 0.744). In addition, the two groups showed similar distribution of the rs8193036 CC (chronic HCV infection: 46.49% vs. healthy controls: 41.98%), CT (45.61% vs. 44.44%) and TT (7.89% vs. 13.58%) genotypes (x2 = 2.346, P = 0.309), and of the rs2275913 AA (16.23% vs. 13.58%), AG (48.25% vs. 50.62%) and GG (35.53% vs. 35.80%) genotypes (x2 = 0.340, P = 0.844). Subgroup analysis of chronic HCV infection patients stratified according to HCV genotypes 1 and 2 showed no differences in the distribution of rs8193036 and rs2275913 alleles (x2 = 1.127, P = 0.288; x2 = 1.088, P = 0.297) and genotypes (x2 = 2.825, P = 0.246; x2 = 0.970, P = 0.616). However, the chronic HCV infection group did show significantly higher levels of serum IL-17 than the controls (97.67+/-39.68 vs. 71.60+/-19.78 pg/ml, t = 2.414, P = 0.033).Chronic HCV infection is associated with increased serum IL-17; however, the IL-17 polymorphisms rs8193036 and rs2275913 were not associated with chronic HCV infection susceptibility in this study's Chinese cohort.

To summarize the clinicopathological manifestations of Wilson disease(WD) so as to improve its recognition.A total of 29 WD cases were retrospectively analyzed, including clinical presentations, liver function test, serum ceruloplasmin, 24 hour urinary copper excretion, ATP7B gene analysis and liver histology. All cases were diagnosed from January 2007 to October 2012 at Third Hospital of Hebei Medical University and China-Japan Friendship Hospital.There were 18 males and 11 females with an average age of 25.9 years. The major clinical symptoms included fatigue (n = 18, 62.1%), abdominal distension (n = 4,13.8%) and pruritus (n = 4, 13.8%). The common physical signs were hepatomegaly (n = 11, 37.9%), splenomegaly(n = 15, 51.7%) and ascites (n = 4, 13.8%). The laboratory examinations included abnormal liver function (n = 29, 100%), high level of 24-hour urinary copper excretion (n = 29, 100.0%), low serum ceruloplasmin (n = 24, 82.8%) and Kayser-Fleischer ring (n = 8, 27.6%). ATP7B gene mutations were at exons 5, 8, 11, 12, 16 and 18. The earliest histologic abnormalities of liver included steatosis (both microvesicular and macrovesicular). Timm's stain showed positive or negative staining. There was no or focal hepatocellular necrosis in liver. During chronic hepatitis phase, the major changes included inflammatory cells infiltration in portal area with biliary epithelium degeneration. The periportal area hepatic cells were swollen, cytoplasm slightly stained and accompanied with some copper particles deposition and cholestic changes. There were many spotty or focal lesion of necrosis in liver. During cirrhotic phase, portal area became enlarged by fibrotic tissue, numerous copper particles deposited in wide fibrous septa and small bile ducts were damaged and became proliferative. Hepatocytes around fibrous interval showed cholestatic changes and contained many copper particles. They diagnosed on the basis of clinical presentation(n = 6), clinical presentation and liver histology (n = 4) and clinical presentation, liver histology and gene analysis (n = 19).There is a high misdiagnosis rate of WD based solely on clinical presentation. Cholestic changes around fibrous interval are common histologic features. The most common ATP7B gene mutations are compound heterozygotes in exons 16. Comprehensive evaluations of clinical presentation, liver histology and gene analysis are helpful for early diagnosis and timely treatment so that it helps to reduce the misdiagnosis and missed diagnosis rate of WD.

To investigate the outcomes of chronic hepatitis C (CHC) patients treated with antiviral regimens of interferon (IFN) plus ribavirin (RBV) using individualized doses and durations.This study was designed as an open-label, prospective clinical trial to analyze the virological responses of 169 CHC patients who received individualized dosages of IFNa-2b or pegylated (Peg)IFNa-2a combined with RBV based on their weight ( less than 60 kg or more than or equal to 60 kg), age (less than 65 years or 65-75 years), morbid state (liver cirrhosis or not), and complications (such as heart disease, diabetes, thyroid disorder). Treatment duration was calculated using the time required to induce HCV RNA negativity. The rates of virological response and adverse effects among the different groups were compared.The IFNa-2b treatment was given to 116 patients, and PegIFNa-2a was given to 53 patients. Compared to the IFNa-2b group, the PegIFNa-2a group showed significantly higher rates of complete early virological response (cEVR; 76.7% vs. 92.5%, P less than 0.05) and sustained virological response (SVR; 53.6% vs. 92.3%, P less than 0.05) among the patients who had completed their course of treatment; the rapid virological response (RVR) rate was also higher for the PegIFNa-2a group but the difference did not reach statistical significance (48.7% vs. 60.4%, P more than 0.05). Seventy-eight patients received the routine dose, and 91 patients received the low dose; there were no significant differences between these two groups for RVR (53.8% vs. 58.9%, P more than 0.05), cEVR (78.0% vs. 80.8%, P more than 0.05), or SVR (65.5% vs. 58.3%, P more than 0.05).Use of an individualized antiviral treatment strategy designed according to the patient's baseline condition, early viral kinetics, and tolerability to adverse reactions can achieve a high rate of SVR, as well as improve the safety, prognosis, and cost-effectiveness associated with treating CHC patients.

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.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.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.Activation of Fas/FasL and its downstream signaling pathway, which induces hepatocellular apoptosis, contributes to the development of alcoholic steatohepatitis and liver fibrosis.

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.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.This study provided evidences for the protective role of activation and overexpression of PPARg in ameliorating hepatocellular apoptosis in mice with hepatic fibrosing steatohepatitis.

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.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).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 value0.001, 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 value0.001. The protein expressions levels of PCNA and TGFb1 were concordant with the mRNA.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.

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-β1, 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.

To investigate the potential role of heme oxygenase-1 on preventing non-alcoholic steatohepatitis (NASH) in mice.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 (P0.01). A contrary effect on serum aminotransferase levels and liver histopathology was observed in mice injected with ZnPP-IX (P0.01).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.