Molecular pathogenesis of metabolic dysfunction-associated steatotic liver disease, steatohepatitis, hepatic fibrosis and liver cirrhosis.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by intense deposition of fat globules in the hepatic parenchyma that could potentially progress to liver cirrhosis and hepatocellular carcinoma. Here, we evaluated a rat model to study the molecular pathogenesis of the spectrum of MASLD and to screen therapeutic agents. SHRSP5/Dmcr rats were fed a high-fat and cholesterol (HFC) diet for a period of 12 weeks and evaluated for the development of steatosis (MASLD), steatohepatitis, fibrosis and cirrhosis. A group of animals were sacrificed at the end of the 4th, 6th, 8th and 12th weeks from the beginning of the experiment, along with the control rats that received normal diet. Blood and liver samples were collected for biochemical and histopathological evaluations. Immunohistochemical staining was performed for α-SMA and Collagen Type I. Histopathological examinations demonstrated steatosis at the 4th week, steatohepatitis with progressive fibrosis at the 6th week, advanced fibrosis with bridging at the 8th week and cirrhosis at the 12th week. Biochemical markers and staining for α-SMA and Collagen Type I demonstrated the progression of steatosis to steatohepatitis, hepatic fibrosis and liver cirrhosis in a stepwise manner. Control animals fed a normal diet did not show any biochemical or histopathological alterations. The results of the present study clearly demonstrated that the HFC diet-induced model of steatosis, steatohepatitis, hepatic fibrosis and cirrhosis is a feasible, quick and appropriate animal model to study the molecular pathogenesis of the spectrum of MASLD and to screen potent therapeutic agents.

Therapeutic implication of human placental extract to prevent liver cirrhosis in rats with metabolic dysfunction-associated steatohepatitis.

Metabolic dysfunction-associated steatohepatitis (MASH) is always accompanied with hepatic fibrosis that could potentially progress to liver cirrhosis and hepatocellular carcinoma. Employing a rat model, we evaluated the role of human placental extract (HPE) to arrest the progression of hepatic fibrosis to cirrhosis in patients with MASH. SHRSP5/Dmcr rats were fed with a high-fat and high-cholesterol diet for 4 weeks and evaluated for the development of steatosis. The animals were divided into control and treated groups and received either saline or HPE (3.6 ml/kg body weight) subcutaneously thrice a week. A set of animals were killed at the end of 6th, 8th, and 12th weeks from the beginning of the experiment. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic malondialdehyde (MDA), and glutathione content were measured. Immunohistochemical staining was performed for α-smooth muscle actin (α-SMA), 4-hydroxy-2-nonenal (4-HNE), collagen type I, and type III. Control rats depicted progression of liver fibrosis at 6 weeks, advanced fibrosis and bridging at 8 weeks, and cirrhosis at 12 weeks, which were significantly decreased in HPE-treated animals. Treatment with HPE maintained normal levels of MDA and glutathione in the liver. There was marked decrease in the staining intensity of α-SMA, 4-HNE, and collagen type I and type III in HPE treated rats compared with control animals. The results of the present study indicated that HPE treatment mediates immunotropic, anti-inflammatory, and antioxidant responses and attenuates hepatic fibrosis and early cirrhosis. HPE depicts therapeutic potential to arrest the progression of MASH towards cirrhosis.

Surgical implantation of human adipose derived stem cells attenuates experimentally induced hepatic fibrosis in rats.

BACKGROUND: Mesenchymal stem cells (MSCs) are multipotent stromal cells and could exert hepatoprotective effects against acute liver injury, steatohepatitis, and fibrogenesis. Here, we evaluated the effects of human adipose derived stem cells (hADSCs) to attenuate experimentally induced hepatic fibrosis and early cirrhosis in rats. METHODS: Hepatic fibrosis was induced by intraperitoneal injections of CCl4 (0.1 ml/100 g body weight) twice a week for 8 weeks. hADSCs were isolated and cultured on polyethylene discs coated with hydroxyapatite and 2 cm diameter disc was surgically implanted on the right lateral lobe of the liver. Discs implanted without hADSCs served as control. The animals were injected again with CCl4 once a week for another 8 weeks. All the animals were sacrificed at the end of 16th week. RESULTS: Serial administrations of CCl4 resulted in well developed fibrosis and early cirrhosis at 8th week which maintained until the 16th week. Animals treated with hADSC discs depicted over 50% decrease of collagen with significant increase in serum albumin and total protein levels. Immunohistochemical staining for TGF-ß1, α-smooth muscle actin, and collagen type I and type III demonstrated marked decrease compared to the animals without hADSC treatment. CONCLUSIONS: Treatment with hADSCs improved liver functions, markedly reduced hepatic fibrosis and early cirrhosis. Various pleiotropic and paracrine factors secreted from the hADSCs seem to serve as reparative functions in the attenuation of liver cirrhosis. The data demonstrated that treatment with hADSCs can be successfully used as a potent therapeutic method to prevent progression of hepatic fibrosis and related adverse events.

The combination of fatty liver and increased gamma-glutamyl transpeptidase levels as a risk factor for atherosclerotic plaque development in apparently healthy people

Background/aim: To elucidate how the combination of fatty liver and increased serum gamma-glutamyl transpeptidase (GGT) levels influences atherosclerotic plaque development in apparently healthy people. Materials and methods: The study population included people who had received an annual health checkup for more than 7 years and had no evidence of carotid plaque at baseline. We investigated the risk factors for carotid plaque occurrence using the Cox proportional hazards model. Results: A total of 107 people (76 men and 31 women; median age, 49 years) were enrolled. At baseline, fatty liver and a serum GGT level ≥50 U/L were observed in 13 and 38 people, respectively. During a median follow-up period of 13.3 years, carotid plaques appeared in 34 people. Multivariate analysis revealed that the combination of fatty liver and a serum GGT level ≥50 U/L was the only significant risk factor for carotid plaque occurrence (age- and sex-adjusted hazard ratio: 5.55; 95% confidence interval 1.70­18.14; P = 0.005). Conclusion: The combination of fatty liver and increased serum GGT levels raises the risk for atherosclerotic plaque development in apparently healthy people.

MMP-13 deletion decreases profibrogenic molecules and attenuates N-nitrosodimethylamine-induced liver injury and fibrosis in mice.

Connective tissue growth factor (CTGF) is involved in inflammation, pathogenesis and progression of liver fibrosis. Matrix metalloproteinase-13 (MMP-13) cleaves CTGF and releases several fragments, which are more potent than the parent molecule to induce fibrosis. The current study was aimed to elucidate the significance of MMP-13 and CTGF and their downstream effects in liver injury and fibrosis. Hepatic fibrosis was induced using intraperitoneal injections of N-nitrosodimethylamine (NDMA) in doses of 10 µg/g body weight on three consecutive days of each week over a period of 4 weeks in both wild-type (WT) and MMP-13 knockout mice. Administration of NDMA resulted in marked elevation of AST, ALT, TGF-ß1 and hyaluronic acid in the serum and activation of stellate cells, massive necrosis, deposition of collagen fibres and increase in total collagen in the liver of WT mice with a significant decrease in MMP-13 knockout mice. Protein and mRNA levels of CTGF, TGF-ß1, α-SMA and type I collagen and the levels of MMP-2, MMP-9 and cleaved products of CTGF were markedly increased in NDMA-treated WT mice compared to the MMP-13 knockout mice. Blocking of MMP-13 with CL-82198 in hepatic stellate cell cultures resulted in marked decrease of the staining intensity of CTGF as well as protein levels of full-length CTGF and its C-terminal fragments and active TGF-ß1. The data demonstrate that MMP-13 and CTGF play a crucial role in modulation of fibrogenic mediators and promote hepatic fibrogenesis. Furthermore, the study suggests that blocking of MMP-13 and CTGF has potential therapeutic implications to arrest liver fibrosis.

An Image Fusion System for Estimating the Therapeutic Effects of Radiofrequency Ablation on Hepatocellular Carcinoma.

BACKGROUND: During ultrasound-guided radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC), high echoic areas due to RFA-induced microbubbles can help calculate the extent of ablation. However, these areas also decrease visualization of target tumors, making it difficult to assess whether they completely cover the tumors. To estimate the effects of RFA more precisely, we used an image fusion system (IFS). PATIENTS AND METHODS: We enrolled patients with a single HCC who received RFA with or without the IFS. In the IFS group, we drew a spherical marker along the contour of a target tumor on reference images immediately after administering RFA so that the synchronized spherical marker represented the contour of the target tumor on real-time ultrasound images. When the high echoic area completely covered the marker, we considered the ablation to be complete. We compared outcomes between the IFS and control groups. RESULTS: We enrolled 25 patients and 20 controls, and the baseline characteristics were similar between the two groups. The complete ablation rates during the first RFA session were significantly higher in the IFS group compared with those in the control group (88.0% vs. 60.0%, P = 0.041). The number of RFA sessions was significantly smaller in the IFS group compared with that in the control group (1.1 ± 0.3 vs. 1.5 ± 0.7, P = 0.016). CONCLUSIONS: The study suggested that the IFS enables a more precise estimation of the effects of RFA on HCC, contributing to enhanced treatment efficacy and minimized patient burden.

GGsTop, a novel and specific γ-glutamyl transpeptidase inhibitor, protects hepatic ischemia-reperfusion injury in rats.

Ischemia-reperfusion (IR) injury is a major clinical problem and is associated with numerous adverse effects. GGsTop [2-amino-4{[3-(carboxymethyl)phenyl](methyl)phosphono}butanoic acid] is a highly specific and irreversible γ-glutamyl transpeptidase (γ-GT) inhibitor. We studied the protective effects of GGsTop on IR-induced hepatic injury in rats. Ischemia was induced by clamping the portal vein and hepatic artery of left lateral and median lobes of the liver. Before clamping, saline (IR group) or saline containing 1 mg/kg body wt of GGsTop (IR-GGsTop group) was injected into the liver through the inferior vena cava. At 90 min of ischemia, blood flow was restored. Blood was collected before induction of ischemia and prior to restoration of blood flow and at 12, 24, and 48 h after reperfusion. All the animals were euthanized at 48 h after reperfusion and the livers were harvested. Serum levels of alanine transaminase, aspartate transaminase, and γ-GT were significantly lower after reperfusion in the IR-GGsTop group compared with the IR group. Massive hepatic necrosis was present in the IR group, while only few necroses were present in the IR-GGsTop group. Treatment with GGsTop increased hepatic GSH content, which was significantly reduced in the IR group. Furthermore, GGsTop prevented increase of hepatic γ-GT, malondialdehyde, 4-hydroxynonenal, and TNF-α while all these molecules significantly increased in the IR group. In conclusion, treatment with GGsTop increased glutathione levels and prevented formation of free radicals in the hepatic tissue that led to decreased IR-induced liver injury. GGsTop could be used as a pharmacological agent to prevent IR-induced liver injury and the related adverse events.

Mural nodule of 10 mm or larger as predictor of malignancy for intraductal papillary mucinous neoplasm of the pancreas: Pathological and radiological evaluations.

BACKGROUND: We had previously reported that mural nodule (MN) ≥10 mm was optimal predictor of malignancy for intraductal papillary mucinous neoplasm (IPMN). However, little is known about its microscopic findings and imaging detectability. METHODS: Medical records and resected specimens of consecutive patients with IPMNs harboring MN ≥ 10 mm were reviewed. Imaging detectability was determined on reports basis. Malignant IPMNs (noninvasive + invasive carcinomas) were microscopically classified according to localization of high-grade dysplasia (HGD) within MN. RESULTS: Thirty-six patients were included. Imaging detectability of MN ≥ 10 mm in CT, MRI, US and EUS were 64%, 68%, 89%, and 97%, respectively. Thirty-three (92%) IPMNs were histologically diagnosed as malignant. Thirty percent of malignant IPMNs were classified into "diffuse HGD within MN", 40% into "focal HGD within MN", and 30% into "HGD outside MN", in which HGD was not located within MN but in low papillary epithelia around MN. Overall sensitivity of pancreatic juice cytology was calculated as 58%, and for "diffuse HGD within MN", "focal HGD within MN", and "HGD outside MN" as 80%, 62%, and 30%, respectively (p = 0.0237). Univariate-analysis showed localization of HGD within MN was associated with true positive cytology (OR = 5.33, p = 0.043). CONCLUSIONS: Detectability of MN ≥ 10 mm is excellent in US and EUS. Although HGD is observed within MN in 70% of malignant IPMNs, HGD is located only in low papillary epithelia around MN in the remaining 30%, in which sensitivity of pancreatic juice cytology is shown to be inadequate.

Imaging morphological changes of intraductal papillary mucinous neoplasm of the pancreas was associated with its malignant transformation but not with development of pancreatic ductal adenocarcinoma.

BACKGROUND/OBJECTIVE: A considerable number of branch duct intraductal papillary mucinous neoplasm (BD-IPMN) developed not infrequently pancreatic malignancy, either as part of IPMN (malignant IPMN) or as concomitant pancreatic ductal adenocarcinoma (PDAC). To date, imaging morphological changes predicting occurrence of malignancy in BD-IPMN are not well-investigated. This study aimed to evaluate the relationships between occurrence of malignancy in BD-IPMN and imaging morphological changes of the tumors observed during follow-up. METHODS: 515 BD-IPMN patients with mural nodule <10 mm and negative cytology were included. 19 patients developed malignant IPMN and 8 patients developed concomitant PDAC during mean follow-up of 4.7 years. The following imaging morphological features were assessed: cyst/main pancreatic duct (MPD) diameter, occurrence of additional cyst/mural nodule. RESULTS: Growth rate of cyst/MPD diameter were significantly larger in patients who developed malignant IPMN compared to those in patients whose IPMN remained benign (p = 0.013, p = 0.01). Occurrence of additional cyst/mural nodule were more frequently observed in patients who developed malignant IPMN (p = 0.009, p = 0.04). In contrast, none of the factors associated with imaging morphological changes of IPMN were shown to be significantly different between patients who developed concomitant PDAC and patients whose IPMN remained benign. Growth rate of MPD diameter and occurrence of additional cyst were independent factors associated with development of malignant IPMN (odds ratio 21.5, and 5.62, respectively). CONCLUSIONS: Imaging morphological changes of IPMN, such as growth rate of MPD diameter and occurrence of additional cyst, could be indicators for development of malignant IPMN, but not for development of concomitant PDAC.

Binge alcohol consumption aggravates oxidative stress and promotes pathogenesis of NASH from obesity-induced simple steatosis.

The pathogenesis of nonalcoholic steatohepatitis (NASH) is a two-stage process in which steatosis is the "first hit" and an unknown "second hit." We hypothesized that "a binge" could be a "second hit" to develop NASH from obesity-induced simple steatosis. Thirty-week-old male Otsuka Long-Evans Tokushima fatty (OLETF) rats were administered 10 mL of 10% ethanol orally for 5, 3, 2, and 1 d/wk for 3 consecutive weeks. As control, male Otsuka Long-Evans Tokushima (OLET) rats were administered the same amount of alcohol. Various biochemical parameters of obesity, steatosis and NASH were monitored in serum and liver specimens in untreated and ethanol-treated rats. The liver sections were evaluated for histopathological alterations of NASH and stained for cytochrome P-4502E1 (CYP2E1) and 4-hydroxy-nonenal (4-HNE). Simple steatosis, hyperinsulinemia, hyperglycemia, insulin resistance, hypertriglycemia and marked increases in hepatic CYP2E1 and 4-HNE were present in 30-wk-old untreated OLETF rats. Massive steatohepatitis with hepatocyte ballooning was observed in the livers of all OLETF rats treated with ethanol. Serum and hepatic triglyceride levels as well as tumor necrosis factor (TNF)-α mRNA were markedly increased in all ethanol-treated OLETF rats. Staining for CYP2E1 and 4-NHE demonstrated marked increases in the hepatic tissue of all the groups of OLETF rats treated with ethanol compared with OLET rats. Our data demonstrated that "a binge" serves as a "second hit" for development of NASH from obesity-induced simple steatosis through aggravation of oxidative stress. The enhanced levels of CYP2E1 and increased oxidative stress in obesity play a significant role in this process.

Predictors of malignancy in branch duct intraductal papillary mucinous neoplasm of the pancreas.

OBJECTIVE: Indication of surgery for branch duct intraductal papillary mucinous neoplasm (BD-IPMN) proposed by the consensus guidelines revised in 2012 was too complex to refer to in clinical practice. This study aimed to identify simple predictors of malignancy in BD-IPMN. METHODS: Consecutive 202 patients with BD-IPMNs were enrolled. They comprised 35 patients that underwent surgery and 167 that were followed up without surgery by being regarded as benign neoplasms. Cutoff values of cyst size, main pancreatic duct (MPD) diameter, and mural nodule size were determined by receiver operator characteristic (ROC) curve. Factors that may discriminate benign from malignant BD-IPMNs were analyzed by multivariate logistic regression model. RESULTS: Cutoff values of cyst size, MPD diameter, and mural nodule size were determined to be 30 mm, 6 mm, and 10 mm, respectively. Multivariate analysis demonstrated that mural nodule ≥10 mm (OR 198, 95% CI 23.1-1690, P<0.0001) and positive cytology (OR 634, 95% CI 49.1-8,190, P<0.0001) were predictors of malignancy in BD-IPMN. When BD-IPMNs with mural nodules ≥10 mm or positive cytology were diagnosed as malignant, sensitivity, specificity, and overall accuracy were 88%, 98%, and 97%, respectively. CONCLUSIONS: Mural nodule ≥10 mm and positive cytology were demonstrated to be simple predictors of malignancy in BD-IPMN.

Cellular and molecular mechanisms of hepatic ischemia-reperfusion injury: The role of oxidative stress and therapeutic approaches.

Ischemia-reperfusion (IR) or reoxygenation injury is the paradoxical exacerbation of cellular impairment following restoration of blood flow after a period of ischemia during surgical procedures or other conditions. Acute interruption of blood supply to the liver and subsequent reperfusion can result in hepatocyte injury, apoptosis, and necrosis. Since the liver requires a continuous supply of oxygen for many biochemical reactions, any obstruction of blood flow can rapidly lead to hepatic hypoxia, which could quickly progress to absolute anoxia. Reoxygenation results in the increased generation of reactive oxygen species and oxidative stress, which lead to the enhanced production of proinflammatory cytokines, chemokines, and other signaling molecules. Consequent acute inflammatory cascades lead to significant impairment of hepatocytes and nonparenchymal cells. Furthermore, the expression of several vascular growth factors results in the heterogeneous closure of numerous hepatic sinusoids, which leads to reduced oxygen supply in certain areas of the liver even after reperfusion. Therefore, it is vital to identify appropriate therapeutic modalities to mitigate hepatic IR injury and subsequent tissue damage. This review covers all the major aspects of cellular and molecular mechanisms underlying the pathogenesis of hepatic ischemia-reperfusion injury, with special emphasis on oxidative stress, associated inflammation and complications, and prospective therapeutic approaches.

Irsogladine maleate for the treatment of recurrent aphthous stomatitis in hepatitis C virus patients on pegylated-interferon and ribavirin: a pilot study.

BACKGROUND AND AIM: Aphthous stomatitis is one of the adverse effects associated with interferon (IFN) that forces dose reduction of IFN and there is no established therapy. This study was aimed to investigate whether irsogladine maleate, which enhances the functions of intercellular communication through the gap junctions, is effective for the treatment of aphthous stomatitis developed in hepatitis C virus (HCV) patients on pegylated-interferon (PEG-IFN) and ribavirin. METHODS: Nineteen patients with HCV were treated with PEG-IFN and ribavirin for 48 weeks. Ten out of 19 patients developed aphthous stomatitis during treatment with PEG-IFN and ribavirin. Within 1-2 weeks after development of aphthous stomatitis, 4 mg irsogladine maleate was orally administered daily to all patients and the therapeutic and adverse effects of irsogladine maleate were examined on every week. The degree of aphthous stomatitis was evaluated by Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. RESULTS: Out of 10 patients, aphthous stomatitis was evaluated as grade 3 in three patients (30%) and grade 2 in seven patients (70%) by CTCAE. CTCAE grade was improved to 0 after 1 week in six patients, after 2 weeks in two patients, and after 3 weeks in two patients after the start of administration of irsogladine maleate. Aphthous stomatitis has not recurred in patients who had been on irsogladine maleate continuously during treatment of PEG-IFN and ribavirin. CONCLUSIONS: Irsogladine maleate is effective for the treatment of aphthous stomatitis developing during PEG-IFN and ribavirin administration in HCV patients.

Chronic ingestion of ethanol induces hepatocellular carcinoma in mice without additional hepatic insult.

BACKGROUND: Chronic intake of alcohol increases the risk of gastrointestinal and hepatic carcinogenesis. The present study was focused to investigate the incidence and mechanism of pathogenesis of hepatocellular carcinoma (HCC) during chronic ingestion of alcohol without any additional hepatic injury. METHODS: Ethanol was administered to Institute for Cancer Research male mice through drinking water for 70 weeks at concentrations of 5 % (first week), 10 % (next 8 weeks), and 15 % thereafter. The animals were killed at 60 and 70 weeks, the livers were examined for hepatic tumors, and evaluated for foci of cellular alteration (FCA). Immunohistochemical staining was performed in the liver sections for cytochrome P4502E1 (CYP2E1), 4-hydroxy-nonenal (4-HNE), and proto-oncogene, c-Myc. RESULTS: At the 60th week, 40 % of the mice in the ethanol group had visible white nodules (5-10 mm) in the liver, but not in the control mice. At the 70th week, several larger nodules (5-22 mm) were present in the livers of 50 % mice in the ethanol group. In the control group, one mouse developed a single nodule. All nodules were histologically trabecular HCC composed of eosinophilic and vacuolated cells. In the livers of both control and ethanol group, several foci with cellular alteration were present, which were significantly higher in ethanol group. Staining for CYP2E1, 4-HNE and c-Myc depicted marked upregulation of all these molecules in the FCA. CONCLUSIONS: Our data demonstrated that upregulation of CYP2E1 and subsequent production of reactive oxygen species along with the persistent expression of c-Myc play a significant role in the pathogenesis of HCC during chronic ingestion of ethanol.

Comparison of the relationships of alcoholic and nonalcoholic fatty liver with hypertension, diabetes mellitus, and dyslipidemia.

We compared the relationships of alcoholic fatty liver and nonalcoholic fatty liver with hypertension, diabetes mellitus, and dyslipidemia. Using a nationwide Japanese survey, we collected data on subjects with biopsy-proven alcoholic fatty liver or nonalcoholic fatty liver. Multiple logistic regression analysis was performed to determine whether alcoholic fatty liver and nonalcoholic fatty liver are associated factors for these diseases. Data on 191 subjects (65, alcoholic fatty liver; 126, nonalcoholic fatty liver) were analyzed. Alcoholic fatty liver (odds ratio, 2.54; 95% confidence interval, 1.06-6.32; p = 0.040), age ≥55 years, and body mass index ≥25 kg/m(2) were correlated with hypertension, whereas nonalcoholic fatty liver (odds ratio, 2.32; 95% confidence interval, 1.08-5.20; p = 0.035) and serum γ-glutamyl transpeptidase levels ≥75 IU/l were correlated with dyslipidemia. Furthermore, we found that there were biological interactions between alcoholic fatty liver and body mass index ≥25 kg/m(2) in ≥55-year-old subjects (attributable proportion due to interaction, 0.68; 95% confidence interval, 0.19-1.17), as well as between alcoholic fatty liver and age ≥55 years in subjects with body mass index ≥25 kg/m(2) (attributable proportion due to interaction, 0.71; 95% confidence interval, 0.24-1.18). Alcoholic fatty liver was more strongly associated with hypertension than nonalcoholic fatty liver and nonalcoholic fatty liver was more strongly associated with dyslipidemia than alcoholic fatty liver. Moreover, alcoholic fatty liver, obesity, and older age may interact to influence hypertension status.

Epigallocatechin-3-gallate inhibits osteopontin expression and prevents experimentally induced hepatic fibrosis.

Osteopontin (OPN) is a matricellular cytokine and a stress-induced profibrogenic molecule that promotes activation of stellate cells during the pathogenesis of hepatic fibrosis. We studied the protective effects of epigallocatechin-3-gallate (EGCG) to suppress oxidative stress, inhibit OPN expression, and prevent experimentally induced hepatic fibrosis. Liver injury was induced with intraperitoneal injections of N-nitrosodimethylamine (NDMA) in a dose of 1 mg/100 g body weight on 3 consecutive days of a week for 28 days. A group of rats received 0.2 mg EGCG/100 g body weight orally everyday during the study. The animals were sacrificed on day 28th from the beginning of exposure. Serum levels of AST, ALT, OPN, malondialdehyde, collagen type IV, and hyaluronic acid were measured. Immunohistochemistry and/or real-time PCR were performed for α-SMA, 4-HNE, OPN, collagen type I, and type III. Serial administrations of NDMA produced well developed fibrosis and early cirrhosis in rat liver. Treatment with EGCG significantly reduced serum/plasma levels of AST, ALT, OPN, malondialdehyde, collagen type IV, and hyaluronic acid and prevented deposition of collagen fibers in the hepatic tissue. Protein and/or mRNA levels demonstrated marked decrease in the expression of α-SMA, 4-HNE, OPN, collagen type I, and type III. Treatment with EGCG prevented excessive generation of reactive oxygen species, suppressed oxidative stress, significantly reduced serum and hepatic OPN levels, and markedly attenuated hepatic fibrosis. The results indicated that EGCG could be used as a potent therapeutic agent to prevent hepatic fibrogenesis and related adverse events.

Novel PKD2 Missense Mutation p.Ile424Ser in an Individual with Multiple Hepatic Cysts: A Case Report.

We report a novel missense mutation, p.Ile424Ser, in the PKD2 gene of an autosomal dominant polycystic kidney disease (ADPKD) patient with multiple liver cysts. A 57-year-old woman presented to our university hospital with abdominal fullness, decreasing appetite, and dyspnea for three months. A percutaneous drainage of hepatic cysts was performed with no significant symptomatic relief. A computed tomography (CT) scan revealed a hepatic cyst in the lateral portion of the liver with appreciable compression of the stomach. Prior to this admission, the patient had undergone three drainage procedures with serial CT-based follow-up of the cysts over the past 37 years. With a presumptive diagnosis of extrarenal manifestation of ADPKD, we performed both a hepatic cystectomy and a hepatectomy. Because the patient reported a family history of hepatic cysts, we conducted a postoperative genetic analysis. A novel missense mutation, p.Ile424Ser, was detected in the PKD2 gene. Mutations in either the PKD1 or PKD2 genes account for most cases of ADPKD. To the extent of our knowledge, this point mutation has not been reported in the general population. Our in-silico analysis suggests a hereditary likely pathogenic mutation.

Association between functional promoter polymorphisms of macrophage migration inhibitory factor (MIF) gene and ulcerative colitis in Japan.

Macrophage migration inhibitory factor (MIF) is a key proinflammatory mediator. Two functional polymorphisms were identified in the promoter region of MIF gene. We attempted to clarify the associations between these polymorphisms and ulcerative colitis (UC). The study was performed in 111 patients with UC and 209 subjects without UC. We employed the PCR-SSCP method to detect gene polymorphisms. Overall, 5/5-CATT genotype was a decreased risk for the development of UC (OR, 0.51; 95% CI, 0.26-0.99). In addition, 7/7-CATT genotype was significantly associated with chronic continuous phenotype and distal colitis phenotype (OR, 5.49; 95% CI, 1.19-25.3, and OR, 6.10; 95% CI, 1.32-28.2, respectively), whereas 5/5-CATT genotype had an inhibitory effect on the development of UC after 20years of age (OR, 0.33; 95% CI, 0.14-0.82). On the other hand, G-173C polymorphism did not affect the susceptibility to and the phenotypes of UC. Our results suggested that tetranucleotide CATT repeat of MIF gene promoter may be associated with the development of UC and the severity of inflammation in patients with UC.

Metabolism of N-nitrosodimethylamine, methylation of macromolecules, and development of hepatic fibrosis in rodent models.

Hepatic fibrosis and cirrhosis are chronic diseases affecting liver and a major health problem throughout the world. The hallmark of fibrosis and cirrhosis is inordinate synthesis and deposition of fibril forming collagens in the extracellular matrix of the liver leading to nodule formation and loss of normal architecture. Hepatic stellate cells play a crucial role in the pathogenesis and progression of liver fibrosis through secretion of several potent fibrogenic factors that trigger hepatocytes, portal fibrocytes, and bone marrow-derived fibroblasts to synthesize and deposit several connective tissue proteins, especially collagens between hepatocytes and space of Disse. Regulation of various events involved in the activation and transformation of hepatic stellate cells seems to be an appropriate strategy for the arrest of hepatic fibrosis and liver cirrhosis. In order to unravel the molecular mechanisms involved in the pathogenesis and progression of hepatic fibrosis, to determine proper and potent targets to arrest fibrosis, and to discover powerful therapeutic agents, a quick and reproducible animal model of hepatic fibrosis and liver cirrhosis that display all decompensating features of human condition is required. This review thoroughly evaluates the biochemical, histological, and pathological features of N-nitrosodimethylamine-induced model of liver injury, hepatic fibrosis, and early cirrhosis in rodents.

Inhibition of γ-glutamyltransferase ameliorates ischaemia-reoxygenation tissue damage in rats with hepatic steatosis.

BACKGROUND AND PURPOSE: Hepatic steatosis may be associated with an increased γ-glutamyltransferase (γ-GT) levels. Ischaemia-reoxygenation (IR) injury causes several deleterious effects. We evaluated the protective effects of a selective inhibitor of γ-GT in experimentally induced IR injury in rats with obesity and steatosis. EXPERIMENTAL APPROACH: Otsuka Long-Evans Tokushima Fatty (OLETF) rats with hepatic steatosis were used in the current study. The portal vein and hepatic artery of left lateral and median lobes were clamped to induce ischaemia. Before clamping, 1 ml of saline (IR group) or 1-ml saline containing 1 mg·kg-1 body weight of GGsTop (γ-GT inhibitor; IR-GGsTop group) was injected into the liver via the inferior vena cava. Blood flow was restored after at 30 min of the start of ischaemia. Blood was collected before, at 30 min after ischaemia and at 2 h and 6 h after reoxygenation. All the animals were killed at 6 h and the livers were collected. KEY RESULTS: Treatment with GGsTop resulted in significant reduction of serum ALT, AST and γ-GT levels and hepatic γ-GT, malondialdehyde, 4-hydroxy-2-nonenal and HMGB1 at 6 h after reoxygenation. Inhibition of γ-GT retained normal hepatic glutathione levels. There was prominent hepatic necrosis in IR group, which is significantly reduced in IR-GGsTop group. CONCLUSION AND IMPLICATIONS: Treatment with GGsTop significantly increased hepatic glutathione content, reduced hepatic MDA, 4-HNE and HMGB1 levels and, remarkably, ameliorated hepatic necrosis after ischaemia-reoxygenation. The results indicated that GGsTop could be an appropriate therapeutic agent to reduce IR-induced liver injury in obesity and steatosis.