Liver cirrhosis

Hepatitis B vs. hepatitis C infection on viral hepatitis-associated hepatocellular carcinoma

BACKGROUND

To determine clinical-pathologic variables in patients with a new diagnosis of hepatocellular carcinoma (HCC) and underlying hepatitis B vs. C infection.

METHODS

Patients presenting to a single urban hospital with a new diagnosis of HCC were entered into a clinical database. Variables including number and size of tumors, presence of metastases, serum alpha-Fetoprotein, hepatitis serologies, severity of hepatic dysfunction, and presence of cirrhosis were evaluated in 127 patients.

RESULTS

Patients with hepatitis B (HBV) were more likely to develop HCC at a younger age than patients with hepatitis C (HCV) (HBV-26% under age 40, HCV-0% under age 40; p < 0.001), with greater serum alpha-Fetoprotein production (median level: HBV-1000 ng/ml vs. HCV-37 ng/ml; p = 0.002), with larger tumors (HBV-78% >5 cm, HCV-28% >5 cm; p < 0.001), in the absence of cirrhosis (HBV-40%, HCV-0%; p < 0.001), and a decreased eligibility for curative treatment (HBV-14%, HCV-34%; p < 0.05). Conversely, patients with HCV were more likely to develop HCC in association with multiple co-morbidities, cirrhosis, and older age.

CONCLUSIONS

Significant clinical-pathologic differences exist among HCC patients with underlying HBV vs. HCV. These differences impact eligibility for potentially-curative therapy and prognosis.

Tissue-specific differences in inflammatory infiltrate and matrix metalloproteinase expression in adipose tissue and liver of mice with diet-induced obesity

AIM

  While low grade inflammation persists in both visceral fat and hepatic tissue in obesity, these changes often result in progressive disease and fibrosis only in the liver and not in adipose tissue. We hypothesized that a tissue-specific difference in obesity-induced inflammatory cell infiltrate may be responsible for such organ difference in susceptibility to fibrosis.

METHODS

  Mice were fed either standard chow or a high fat diet over 19 weeks. Hepatic steatosis was assessed by histology and quantified via magnetic resonance spectroscopy. Immunohistochemistry staining for macrophage subsets and quantitative reverse transcription-polymerase chain reaction for matrix metalloproteinase (MMP)- and fibrosis-related gene expression was performed in paired livers and visceral (epididymal) fat pads at early (9 weeks) and advanced (19 weeks) stages of progressive diet-induced obesity.

RESULTS

  Up to 19 weeks of high fat feeding led to the development of obesity and hepatic steatosis, as well as increased gene expression of Mmp12, Mmp13 and Timp1 in predominantly adipose tissue, and to a lesser extent of liver tissue. In contrast to visceral fat, cell counts for macrophages as well as profibrogenic gene signaling in liver tissue during development of diet-induced obesity remained largely unchanged.

CONCLUSIONS

  Development of diet-induced obesity in the mouse increased inflammatory macrophages counts in adipose tissue rather than the liver. This was associated with greater increases in MMP expression in adipose tissue compared with liver. We propose that attenuated hepatic MMP expression in livers and adipose tissue of obese mice shifts the balance of fibrogenesis/fibrolysis and predispose the liver to development of fibrosis.

Different patterns of decompensation in patients with alcoholic vs. non-alcoholic liver cirrhosis

BACKGROUND

The histological pattern of fibrosis in liver cirrhosis varies in different chronic liver diseases, and hepatic decompensation may be differentiated in consequences of fibrosis (i.e. ascites, variceal bleeding) or in lack of function (i.e. jaundice) resulting in aetiology-specific variable morbidity and mortality.

AIM

To evaluate patterns of hepatic decompensation in relation to the aetiology of liver cirrhosis.

METHODS

Two different cohorts were retrospectively evaluated between 2002 and 2007. Cohort A was for hypothesis generation and consisted of 220 cirrhotic patients. To confirm the initial observations a second cohort B (n = 217) was analysed. The different patterns of hepatic decompensation evaluated were ascites, jaundice, encephalopathy, variceal bleeding, spontaneous bacterial peritonitis, hepatorenal syndrome or hepatocellular carcinoma. Furthermore, we analysed survival in relation to pattern of decompensation in alcoholic vs. non-alcoholic liver disease.

RESULTS

Alcoholics were more frequently hospitalised for ascites (cohort A: 81.4% vs. 65.4%, P = 0.016; cohort B 71.3% vs. 58.5%, P = 0.085). In contrast, non-alcoholics presented with higher rates of hepatocellular carcinoma (cohort A: 23.1% vs. 11.9%, P = 0.046; cohort B 38.6% vs. 22.5%, P = 0.018). There were no significant differences in jaundice, variceal bleeding, hepatorenal syndrome or encephalopathy. Survival was significantly impaired in non-alcoholic cirrhosis once ascites occurred (P = 0.003), whereas ascites did not predict higher mortality in patients with alcoholic cirrhosis.

CONCLUSIONS

Ascites is the leading initial pattern of decompensation in alcoholic cirrhosis whereas hepatocellular carcinoma dominates in non-alcoholics. Non-alcoholics developing ascites show a poor survival.

Incidence, etiology and mortality of cirrhosis: a population-based cohort study

OBJECTIVE

Knowledge on the prognosis among patients with cirrhosis is mainly based on clinical trials with selected patient groups as well as population-based register studies with suboptimal diagnostic reliability. The aim of the study was to describe incidence, etiology, and mortality of well-validated cirrhotic cases in a population-based cohort at Funen (population 470,000) between 1996 and 2006.

MATERIALS AND METHODS

A population-based cohort study with case identification from discharge diagnosis followed by manual validation of patient records with inclusion of cases that fulfilled predefined diagnostic criteria.

RESULTS

4010 possible cases were identified. 1369 patients were included, 67% males, mean age 56.4 years, 75% had cirrhotic complications at entry. Mean follow-up was 3.6 years with a total of 4976 years of follow-up. The incidence was 33/100,000 person-years (95% confidence interval CI 28-40). Stratified for age and sex, the incidence was twice as high for men compared with women in all age groups. The five-year mortality was 62% (95% CI 59-65). A multivariate analysis showed a high mortality associated with male gender (HR 1.24, 95% CI 1.08-1.42), ages above 70 years (HR 2.01 95% CI 1.65-2.47) compared with ages 50-59 years, complications present at diagnosis (HR 1.28, 95% CI 1.09-1.50) and etiology of alcoholic disease or cryptogenic cirrhosis (HR 2.38, 95% CI 1.22-4.67 and 2.26, 95% CI 1.13-4.53).

CONCLUSIONS

Incidence of cirrhosis is higher among men than among women. High age, male gender, alcoholic cirrhosis, cryptogenic cirrhosis, and complications at the time of diagnosis increased mortality.

The end-organ impairment in liver cirrhosis: appointments for critical care

Liver cirrhosis (LC) can lead to a clinical state of liver failure, which can exacerbate through the course of the disease. New therapies aimed to control the diverse etiologies are now more effective, although the disease may result in advanced stages of liver failure, where liver transplantation (LT) remains the most effective treatment. The extended lifespan of these patients and the extended possibilities of liver support devices make their admission to an intensive care unit (ICU) more probable. In this paper the LC is approached from the point of view of the pathophysiological alterations present in LC patients previous to ICU admission, particularly cardiovascular, but also renal, coagulopathic, and encephalopathic. Infections and available liver detoxifications devices also deserve mentioning. We intend to contribute towards ICU physician readiness to the care for this particular type of patients, possibly in dedicated ICUs.

The microenvironment in hepatocyte regeneration and function in rats with advanced cirrhosis

In advanced cirrhosis, impaired function is caused by intrinsic damage to the native liver cells and from the abnormal microenvironment in which the cells reside. The extent to which each plays a role in liver failure and regeneration is unknown. To examine this issue, hepatocytes from cirrhotic and age-matched control rats were isolated, characterized, and transplanted into the livers of noncirrhotic hosts whose livers permit extensive repopulation with donor cells. Primary hepatocytes derived from livers with advanced cirrhosis and compensated function maintained metabolic activity and the ability to secrete liver-specific proteins, whereas hepatocytes derived from cirrhotic livers with decompensated function failed to maintain metabolic or secretory activity. Telomere studies and transcriptomic analysis of hepatocytes recovered from progressively worsening cirrhotic livers suggest that hepatocytes from irreversibly failing livers show signs of replicative senescence and express genes that simultaneously drive both proliferation and apoptosis, with a later effect on metabolism, all under the control of a central cluster of regulatory genes, including nuclear factor κB and hepatocyte nuclear factor 4α. Cells from cirrhotic and control livers engrafted equally well, but those from animals with cirrhosis and failing livers showed little initial evidence of proliferative capacity or function. Both, however, recovered more than 2 months after transplantation, indicating that either mature hepatocytes or a subpopulation of adult stem cells are capable of full recovery in severe cirrhosis.

CONCLUSION

Transplantation studies indicate that the state of the host microenvironment is critical to the regenerative potential of hepatocytes, and that a change in the extracellular matrix can lead to regeneration and restoration of function by cells derived from livers with end-stage organ failure.

Meta-analysis: beta-blockers versus banding ligation for primary prophylaxis of esophageal variceal bleeding

AIM

To perform an updated meta-analysis comparing β-blockers (BB) with endoscopic variceal banding ligation (EVBL) in the primary prophylaxis of esophageal variceal bleeding.

MATERIAL AND METHODS

Randomized controlled trials were identified through electronic databases, article reference lists and conference proceedings. Analysis was performed using both fixed-effect and random-effect models. Heterogeneity and publication bias were systematically taken into account. Main outcomes were variceal bleeding rates and all-cause mortality, calculated overall and at 6, 12, 18 and 24 months.

RESULTS

19 randomized controlled trials were analyzed including a total of 1,483 patients. Overall bleeding rates were significantly lower for the EVBL group: odds ratio (OR) 2.06, 95% confidence interval (CI) [1.55-2.73], p < 0.0001, without evidence of publication bias. Bleeding rates were also significantly lower at 18 months (OR 2.20, 95% CI [1.04-4.60], P = 0.04), but publication bias was detected. When only high quality trials were taken into account, results for bleeding rates were no longer significant. No significant difference was found for either bleeding-related mortality or for all-cause mortality overall or at 6, 12, 18 or 24 months. BB were associated with more frequent severe adverse events (OR 2.61, 95% CI 1.60-4.40, P < 0.0001) whereas fatal adverse events were more frequent with EVBL (OR 0.14, 95% CI 0.02-0.99, P = 0.05).

CONCLUSION

EVBL appears to be superior to BB in preventing the first variceal bleed, although this finding may be biased as it was not confirmed by high quality trials. No difference was found for mortality. Current evidence is insufficient to recommend EVBL over BB as first-line therapy.

Promotion of hepatocellular carcinoma by the intestinal microbiota and TLR4

Increased translocation of intestinal bacteria is a hallmark of chronic liver disease and contributes to hepatic inflammation and fibrosis. Here we tested the hypothesis that the intestinal microbiota and Toll-like receptors (TLRs) promote hepatocellular carcinoma (HCC), a long-term consequence of chronic liver injury, inflammation, and fibrosis. Hepatocarcinogenesis in chronically injured livers depended on the intestinal microbiota and TLR4 activation in non-bone-marrow-derived resident liver cells. TLR4 and the intestinal microbiota were not required for HCC initiation but for HCC promotion, mediating increased proliferation, expression of the hepatomitogen epiregulin, and prevention of apoptosis. Gut sterilization restricted to late stages of hepatocarcinogenesis reduced HCC, suggesting that the intestinal microbiota and TLR4 represent therapeutic targets for HCC prevention in advanced liver disease.

Soluble urokinase plasminogen activator receptor is associated with progressive liver fibrosis in hepatitis C infection

BACKGROUND

Progressive liver fibrosis is the main predictor of disease outcome in chronic hepatitis C viral (HCV) infection. Although the importance of the coagulation cascade has been suggested in liver fibrogenesis, the role of the fibrinolytic pathway is yet unclear.

GOAL

We evaluated the association of serum levels of the fibrinolysis-associated soluble urokinase plasminogen activator receptor (suPAR) with the severity of liver fibrosis in HCV infection.

STUDY

suPAR serum levels were assessed in 146 chronically HCV-infected patients of 2 independent cohorts (64 subjects in the screening cohort, 82 in the validation cohort) by enzyme-linked immunosorbent assay and correlated with biopsy-proven histologic stage of liver fibrosis and noninvasive liver fibrosis markers (aspartate transaminase to platelets ratio index score, transient elastography).

RESULTS

suPAR serum levels were strongly associated with the histologic stage of liver fibrosis in both cohorts (P<0.0001). Although mean suPAR levels in patients with F1 and F2 fibrosis were not different from healthy control subjects, they were significantly increased at higher stages of liver fibrosis (F3 and F4, P<0.0001). suPAR values had a high diagnostic specificity and sensitivity to differentiate mild/moderate fibrosis (F1/F2) from severe fibrosis (F3/F4) with an area under curve of 0.774 (P=0.0001) and for the differentiation of noncirrhosis from cirrhosis (F1/F2/F3 vs. F4, area under curve 0.791, P=0.0001). SuPAR serum levels were also strongly correlated to the noninvasive fibrosis markers aspartate transaminase to platelets ratio index score (r=0.52) and transient elastography (r=0.44, both P<0.0001).

CONCLUSIONS

Serum suPAR levels were robust markers of liver fibrosis in 2 cohorts with a comparable diagnostic accuracy for prediction of severe liver fibrosis as established noninvasive marker.

A population-based study of hepatitis D virus as potential risk factor for hepatocellular carcinoma

Hepatitis D virus (HDV) is dependent on the presence of hepatitis B virus (HBV) for transmission and replication because of its inability to produce its own coat. It remains unclear whether HDV infection increases the risk of hepatocellular carcinoma. Using the Swedish Hospital Discharge Register and Outpatient Registry, we identified 9160 patients with chronic HBV infection between 1997 and 2008, of whom 327 had chronic HDV infection and 323 had acute HDV infection. Standardized incidence ratios (SIRs) were calculated for these patients compared with the general population. The risk of hepatocellular carcinoma was greatly increased in patients with HBV and HDV (SIR = 137.17, 95% confidence interval [CI] = 62.19 to 261.51). The risk of hepatocellular carcinoma among patients with HBV and HDV was increased (SIR = 6.11, 95% CI = 2.77 to 11.65) when patients with chronic HBV infection alone were used as the reference population. Similar results were observed for patients with chronic HDV infection (SIR = 99.26, 95% CI = 42.39 to 196.55). Our findings indicate that HDV is a strong risk factor for hepatocellular carcinoma.

Micro-RNA profiling in human serum reveals compartment-specific roles of miR-571 and miR-652 in liver cirrhosis

BACKGROUND AND AIMS

Micro-RNAs (miRNAs) have recently emerged as crucial modulators of molecular processes involved in chronic liver diseases. The few miRNAs with previously proposed roles in liver cirrhosis were identified in screening approaches on liver parenchyma, mostly in rodent models. Therefore, in the present study we performed a systematic screening approach in order to identify miRNAs with altered levels in the serum of patients with chronic liver disease and liver cirrhosis.

METHODS

We performed a systematic, array-based miRNA expression analysis on serum samples from patients with liver cirrhosis. In functional experiments we evaluated the relationship between alterations of miRNA serum levels and their role in distinct cellular compartments involved in hepatic cirrhosis.

RESULTS

The array analysis and the subsequent confirmation by qPCR in a larger patient cohort identified significant alterations in serum levels of miR-513-3p, miR-571 and miR-652, three previously uncharacterized miRNAs, in patients with alcoholic or hepatitis C induced liver cirrhosis. Of these, miR-571 serum levels closely correlated with disease stages, thus revealing potential as a novel biomarker for hepatic cirrhosis. Further analysis revealed that up-regulation of miR-571 in serum reflected a concordant regulation in cirrhotic liver tissue. In isolated primary human liver cells, miR-571 was up-regulated in human hepatocytes and hepatic stellate cells in response to the pro-fibrogenic cytokine TGF-β. In contrast, alterations in serum levels of miR-652 were stage-independent, reflecting a concordant down-regulation of this miRNA in circulating monocytes of patients with liver cirrhosis, which was inducible by proinflammatory stimuli like bacterial lipopolysaccharide.

CONCLUSION

Alterations of miR571 and miR-652 serum levels in patients with chronic liver disease reflect their putative roles in the mediation of fibrogenic and inflammatory processes in distinct cellular compartments involved in the pathogenesis of liver cirrhosis.

Genomic risk of hepatitis C-related hepatocellular carcinoma

To identify the genetic susceptibility factor(s) for hepatitis C virus-induced hepatocellular carcinoma (HCV-induced HCC), we conducted a genome-wide association study using 432,703 autosomal SNPs in 721 individuals with HCV-induced HCC (cases) and 2890 HCV-negative controls of Japanese origin. Eight SNPs that showed possible association (P <1 10(⁻5)) in the genome-wide association study were further genotyped in 673 cases and 2596 controls. We found a previously unidentified locus in the 50 flanking region of MICA on 6p21.33 (rs2596542, P(combined) = 4.21 10(⁻13), odds ratio = 1.39) to be strongly associated with HCV induced HCC. Subsequent analyses using individuals with chronic hepatitis C (CHC) indicated that this SNP is not associated with CHC susceptibility (P = 0.61) but is significantly associated with progression from CHC to HCC (P = 3.13 10(⁻8)). We also found that the risk allele of rs2596542 was associated with lower soluble MICA protein levels in individuals with HCV-induced HCC (P = 1.38 10(⁻13)).

Comparison of circulating endothelial cell/platelet count ratio to aspartate transaminase/platelet ratio index for identifying patients with cirrhosis

BACKGROUND/OBJECTIVES

Circulating endothelial cells (CECs) are indicative of vascular injury and correlate with severity of vascular diseases. A pilot study showed that the ratio of CEC to platelet count (CEC/PC) was effective in predicting cirrhosis. Therefore, we evaluated CEC/PC in a larger cohort of patients, correlated it with cirrhosis, and compared its operating characteristics with previously described biomarker for cirrhosis, the AST/platelet ratio index (APRI).

METHODS

Fifty-three patients with cirrhosis, 20 matched healthy controls, and 9 patients with noncirrhotic liver disease were recruited. Peripheral blood sample was collected and analyzed to enumerate nucleated CEC CD146+, CD105+, CD45- using a commercial assay.

RESULTS

Median CEC counts were significantly higher in patients with cirrhosis (62 cells/4 mL, interquartile range [IQR]: 43.5-121) as compared with controls (31 cells/4 mL, IQR: 22.2-40). The CEC/PC was also significantly elevated in cirrhotics (0.69, IQR: 0.39-1.48) compared with controls (0.12, IQR: 0.09-0.20) and noncirrhotics (0.21, IQR: 0.08-0.43). Receiver operator characteristic (ROC) analysis revealed that CEC cutoff value of ≥37 cells/4 mL showed sensitivity of 81% and specificity of 75% for differentiating cirrhosis from controls (area under the curve [AUC]: 0.80; 95% confidence interval [CI] 0.67-0.91). The CEC/PC ratio cutoff value of ≥0.23 showed sensitivity of 91% and specificity of 82% (AUC: 0.92; 95% CI 0.83-0.99). The APRI cutoff value of ≥0.4 showed sensitivity of 94% and specificity of 85% for differentiating cirrhosis from control patients (AUC: 0.96; 95% CI 0.90-1.0). A product of CEC and APRI, termed CAPRI (CEC-APRI), effectively distinguished patients with cirrhosis from controls; with cutoff value of ≥12.7, showing higher sensitivity of 98% and specificity of 85% (AUC: 0.98; 95% CI 0.96-1.0).

CONCLUSION

The CEC/PC ratio is significantly elevated in patients with cirrhosis and demonstrates comparable operating characteristics to previously described APRI. Furthermore, CAPRI, compiled as product of CEC to APRI showed outstanding ability to distinguish patients with cirrhosis from controls, although larger studies are necessary for validation.

Feasibility of semiquantitative liver perfusion assessment by ferucarbotran bolus injection in double-contrast hepatic MRI

PURPOSE

To evaluate the feasibility of semiquantitative measurement of liver perfusion from analysis of ferucarbotran induced signal-dynamics in double-contrast liver MR-imaging (DC-MRI).

MATERIALS AND METHODS

In total 31 patients (21 men; 58 ± 10 years) including 18 patients with biopsy proven liver cirrhosis prospectively underwent clinically indicated DC-MRI at 1.5 Tesla (T) with dynamic T2-weighted gradient-echo imaging after ferucarbotran bolus injection. Breathing artefacts in tissue and input time curves were reduced by Savitzky-Golay-filtering and semiquantitative perfusion maps were calculated using a model free approach. Hepatic blood flow index (HBFI) and splenic blood flow index (SBFI) were determined by normalization of arbitrary perfusion values to the perfusion of the erector spinae muscle resulting in a semiquantitative perfusion measure.

RESULTS

In 30 of 31 patients the evaluated protocol could successfully be applied. Mean HBF was 7.7 ± 2.46 (range, 4.6-12.8) and mean SBF was 13.20 ± 2.57 (range, 8.5-17.8). A significantly lower total HBF was seen in patients with cirrhotic livers as compared to patients with noncirrhotic livers (P < 0.05). In contrast, similar SBF was observed in cirrhotic and noncirrhotic patients (P = 0.11).

CONCLUSION

Capturing the signal dynamics during bolus injection of ferucarbotran in DC-MRI of the liver allows for semiquantitative assessment of hepatic perfusion that may be helpful for a more precise characterisation of liver cirrhosis and focal liver lesions.

"Normal" liver stiffness measure (LSM) values are higher in both lean and obese individuals: a population-based study from a developing country

The liver stiffness measure (LSM) needs to be explored in ethnically and anthropometrically diverse healthy subjects (to derive an acceptable normal range) and also in patients with liver disease. In view of this objective, LSM was performed by transient elastography (TE) using FibroScan in 437 healthy subjects with normal alanine aminotransferase (ALT) levels, recruited from a free-living population of the Birbhum Population Project (BIRPOP; www.shds.in), a Health and Demographic Surveillance System (HDSS), and from 274 patients with liver disease attending the Hepatology Clinic of the School of Digestive and Liver Diseases (SDLD; Institute of Post Graduate Medical Education & Research [IPGME&R], Kolkata, India) including 188 with nonalcoholic fatty liver disease (NAFLD) and 86 with chronic hepatitis of viral and other etiologies. Liver biopsy was performed in 125 patients. The range of normal values for LSM, defined by 5th and 95th percentile values in healthy subjects, was 3.2 and 8.5 kPa, respectively. Healthy subjects with a lower body mass index (BMI; < <18.5 kg/m(2)) had a higher LSM compared with subjects who had a normal BMI; this LSM value was comparable to that of obese subjects (6.05 ± 1.78 versus 5.51 ± 1.59 and 6.60 ± 1.21, P = 0.016 and 0.349, respectively). Liver disease patients without histologic fibrosis had significantly higher LSM values compared with healthy subjects (7.52 ± 5.49 versus 5.63 ± 1.64, P < 0.001). Among the histologic variables, stage of fibrosis was the only predictor for LSM. LSM did not correlate with inflammatory activity and ALT in both NAFLD and chronic hepatitis groups.

CONCLUSION

LSM varies between 3.2 and 8.5 kPa in healthy subjects of South Asian origin. Both lean and obese healthy subjects have higher LSM values compared with subjects with normal BMI. Liver stiffness begins to increase even before fibrosis appears in patients with liver disease.

High prevalence of autoantibodies to C-reactive protein in patients with chronic hepatitis C infection: association with liver fibrosis and portal inflammation

The presence of autoantibodies against C-reactive protein (anti-CRP) has been reported in association with autoimmunity and histopathology in chronic hepatitis C virus (HCV) infection. Resistin could play a role in the pathogenesis of hepatitis, although results on HCV infection are ambiguous. Here we retrospectively analyzed anti-CRP and resistin levels in the sera of 38 untreated and well-characterized HCV patients at the time of their first liver biopsy. HCV activity and general health were assessed by a physician at least yearly until follow-up ended. Anti-CRP and resistin were also measured in patients with autoimmune hepatitis (AIH) and nonalcoholic fatty liver disease (NAFLD). Anti-CRP antibodies were registered in all HCV patients, whereas only a few AIH (11%) and NAFLD (12%) sera were positive. Anti-CRP levels were related to histopathological severity and were highest in patients with cirrhosis at baseline. Resistin levels were similar in HCV, AIH, and NAFLD patients, but high levels of resistin were associated with early mortality in HCV patients. Neither anti-CRP nor resistin predicted a response to interferon-based therapy or cirrhosis development or was associated with liver-related mortality. We conclude that anti-CRP antibodies are frequently observed in chronic HCV infection and could be a useful marker of advanced fibrosis and portal inflammation.

Induction of heme oxygenase 1 prevents progression of liver fibrosis in Mdr2 knockout mice

Induction or overexpression of the heme-degrading enzyme, heme oxygenase 1 (HO-1), has been shown to protect mice from liver damage induced by acute inflammation. We have investigated the effects of HO-1 induction in a mouse model of chronic liver inflammation and fibrogenesis with progression to hepatocellular carcinoma (HCC) (Mdr2ko; FVB.129P2-Abcb4(tm1Bor)). HO-1 was induced in vivo by treatment with cobalt protoporphyrin IX, starting at week 5 or 12 of mice lifespan, and continued for 7 weeks. Our results showed that HO-1 induction reduced liver damage and chronic inflammation by regulating immune cell infiltration or proliferation as well as tumor necrosis factor receptor signaling. Fibrosis progression was significantly reduced by HO-1 induction in mice with mild, as well as established, portal and lobular fibrosis. HO-1 induction significantly suppressed hepatic stellate cell activation. During established fibrosis, HO-1 induction was able to revert portal inflammation and fibrosis below levels observed at the start of treatment. Moreover, hepatocellular proliferation and signs of dysplasia were decreased after HO-1 induction.

CONCLUSION

Induction of HO-1 interferes with chronic inflammation and fibrogenesis and, in consequence, might delay progression to HCC.

Effects of Chinese herbal cataplasm Xiaozhang Tie on cirrhotic ascites

BACKGROUND

Conventional methods of treating cirrhotic ascites are inadequate. We sought to identify a novel, effective approach to relieve the suffering of patients with cirrhotic ascites.

AIM OF THE STUDY

To investigate the efficacy of Xiaozhang Tie, a traditional Chinese herbal cataplasm composed of dahuang (Rheum palmatum L.), laifuzi (Raphanus sativus L.), concocted gansui (Euphorbia kansui T.N. Liou ex T.P. Wang), chenxiang [Aquilaria sinensis (Lour.) Gilg], dingxiang (Eugenia caryophyllata Thunb.), bingpian (Borneolum syntheticum) and shexiang (artificial Moschus), as an adjuvant in treating cirrhotic ascites.

MATERIALS AND METHODS

A multicenter, randomized, placebo-controlled trial was conducted. One hundred patients with cirrhotic ascites were divided into two groups of equal size. The test group took an umbilical compress with Xiaozhang Tie for 30 days while the control group was administered an umbilical compress with placebo, in addition to primary therapy. Efficacy was evaluated according to the criteria including ascites volume, urine 24-h volume, abdominal circumference, body weight, abdominal distention, appetite, flatus and defecation.

RESULTS

Ninety-two patients completed the study, 7 were withdrawn and 1 was excluded. The effective rate of grades I and II was 63.3% for the test group (n=49) and 38.0% for the control one (n=50). Both groups showed decreased body weight and abdominal circumference, increased urine volume and improved symptoms after treatment. However, the differences between pre-treatment and post-treatment in body weight, abdominal circumference and urine volume were 8.7±5.8 kg, 12.4±8.3 cm and 683±644 ml respectively in the test group, noticeably higher than those in the control group, which were 5.3±4.6 kg, 8.0±6.5 cm and 372±697 ml, respectively. The ranking orders of the symptoms of the test group were significantly lower than those of the control group after treatment. No severe adverse reactions were seen.

CONCLUSION

Xiaozhang Tie as an adjuvant to primary therapy of cirrhotic ascites is safe and shows a remarkable efficacy on relieving abdominal distention.

1H NMR-based serum metabolic profiling in compensated and decompensated cirrhosis

AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients.

METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients (n = 30), decompensated cirrhosis patients (n = 30) and healthy controls (n = 30). A ¹H nuclear magnetic resonance (NMR)-based metabonomics approach was used to obtain the serum metabolic profiles of the samples. The acquired data were processed by multivariate principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA).

RESULTS: The OPLS-DA model was capable of distinguishing between decompensated and compensated cirrhosis patients, with an R²Y of 0.784 and a Q²Y of 0.598. Twelve metabolites, such as pyruvate, phenylalanine and succinate, were identified as the most influential factors for the difference between the two groups. The validation of the diagnosis prediction showed that the accuracy of the OPLS-DA model was 85% (17/20).

CONCLUSION: ¹H NMR spectra combined with pattern recognition analysis techniques offer a new way to diagnose compensated and decompensated cirrhosis in the future.

Comparison of three algorithms of non-invasive markers of fibrosis in chronic hepatitis C

BACKGROUND

Preliminary data suggest that performance of non-invasive markers for liver fibrosis in hepatitis C may improve when combined. Three algorithms based on the combination of Fibrotest, Forns' index and AST-to-platelet ratio (APRI) have been proposed: Sequential Algorithm for Fibrosis Evaluation (SAFE biopsy); Fibropaca algorithm; Leroy algorithm.

AIM

To compare three algorithms to diagnose significant fibrosis (≥ F2 by METAVIR) and cirrhosis (F4).

METHODS

A total of 1013 HCV monoinfected cases undergoing liver biopsy were consecutively enrolled in seven centres. Fibrotest, APRI and Forns' index were measured at the time of liver biopsy, considered the reference standard.

RESULTS

Overall, performance of combination algorithms was significantly higher than the single non-invasive methods (P < 0.0001). SAFE biopsy and Fibropaca algorithm saved a significantly higher number of liver biopsies than the single methods (P < 0.0001). For ≥ F2, Fibropaca algorithm saved more biopsies than SAFE biopsy (51.7% vs. 43.8%, P = 0.0003), but with lower accuracy (87.6% vs. 90.3%, P = 0.05). Regarding F4, the number of saved liver biopsies did not differ between SAFE biopsy and Fibropaca algorithm (79.1% vs. 76.2%, P = 0.12). However, SAFE biopsy showed a lower accuracy when compared with Fibropaca algorithm (91.2% vs. 94%, P = 0.02). As to Leroy algorithm, although it showed a good performance for ≥ F2 (93.5% accuracy), it saved less liver biopsies than SAFE biopsy and Fibropaca algorithm (29.2% vs. 43.8% and 51.7% respectively, P < 0.0001).

CONCLUSIONS

SAFE biopsy and the Fibropaca algorithm have excellent performance for liver fibrosis in hepatitis C, allowing a significant reduction in the need for liver biopsies. They can be useful in clinical practice and for large-scale screening.

Is water diffusion isotropic in the cirrhotic liver? a study with diffusion-weighted imaging at 3.0 Tesla

RATIONALE AND OBJECTIVES

Water molecule motion has been shown to be isotropic in healthy liver as assessed by diffusion-weighted imaging (DWI). The purpose of this study was to investigate whether this assumption is still valid in the cirrhotic liver.

MATERIALS AND METHODS

Twelve cirrhotic patients and 12 controls underwent DWI on a 3.0T-system. We used an echo-planar sequence independently applying unidirectional motion-probing gradients along read-(x), phase-(y), and slice-(z) directions, respectively. Liver apparent diffusion coefficient (ADC) and perfusion fraction (f) were calculated along each gradient direction, based on two b-values sets (0-400 and 0-800 seconds/mm(2)). Measurement was repeated at two different axial slices of the liver.

RESULTS

No significant difference among x, y, and z- ADC (and f) of the liver was found within controls and cirrhotic patients (P > .01), regardless of the set of b-values or the slice of measurement. ADC was lower in cirrhotic patients than in controls (difference of 0.24-0.39 × 10(-3) mm(2)/seconds at b = 800 seconds/mm(2); P = .000-.0139). Perfusion fraction f was lower in cirrhotics than in controls, irrespective of the b-values set or the slice of measurement (difference of 0.05-0.15; P < .0001-.0885).

CONCLUSION

The liver shows isotropic water diffusion in cirrhotics, despite fibrotic distortion leading to decreased ADC as compared to controls. Our results emphasize that the correlation between parenchymal changes in liver fibrosis and the ADC estimate remains an elusive goal based on the state-of-the-art DWI technique.

Living donor liver transplantation for hepatocellular carcinoma: the Japanese experience

Treatment strategies against hepatocellular carcinoma have progressed remarkably over the past decade. In Asia, evidence-based guidelines for the management of hepatocellular carcinoma have evolved, including the option of liver transplantation. Due to severe organ shortage, however, living donor liver transplantation has become mainstream in Japan. Unlike deceased donor transplantation, living donor transplantation is not limited by the restrictions imposed by the nationwide allocation system. The decision for transplantation often depends on institutional or case-by-case considerations, balancing the will of the donor, the operative risk, and the overall survival benefit for the recipient. Cumulative data from the national multicenter registry analysis as well as individual center experience suggest that expansion of the Milan criteria is warranted.

Editorial: staging liver fibrosis in hepatitis C: a challenge for this decade

The limitations of and the invasive nature of liver biopsy has spurred extensive interest in the development of non-invasive tests to measure liver fibrosis in patients with chronic hepatitis C. Clinically applicable non-invasive tests, including radiological studies, elastography, and serum markers, all of which perform extremely well in excluding significant disease and diagnosing cirrhosis. FibroScan and acoustic radiation force impulse elastography are two elastography-based tests that show promise. In this new era of increased cure rates with newly Food and Drug Administration-approved drugs and the availability of multiple non-invasive tests of liver fibrosis, we anticipate a decreasing need for liver biopsies in the management of chronic hepatitis C.

Nonalcoholic steatohepatitis: the therapeutic challenge of a global epidemic

PURPOSE OF REVIEW

Nonalcoholic fatty liver (NAFL) and especially its inflammatory variant nonalcoholic steatohepatitis (NASH) have become a major challenge to healthcare systems worldwide because of the increasing prevalence of its major risk factors obesity and type 2 diabetes, which are closely linked to overeating, physical inactivity, and the metabolic syndrome.

RECENT FINDINGS

Between 10 and 20% of patients with NAFL develop NASH, which can progress to cirrhosis, end-stage liver disease, and hepatocellular carcinoma. The overall mortality in these patients is significantly increased because of both cardiovascular and liver-related complications. Sustained weight loss by diet and exercise, which is the most effective therapeutic measure, is only achieved by a minority of patients, having led to a great yet unmet need for medical therapies of NASH.

SUMMARY

Pharmacological therapies should target the underlying pathophysiology that involves insulin resistance, enhanced peripheral lipolysis and release of free fatty acids, oxidative stress, accumulation of toxic lipids, adipose tissue inflammation, sensitization of hepatocytes toward apoptotic cell death, and fibrogenesis. However, pharmacological therapy that is well tolerated, cost-effective, and poses an acceptable risk-to-benefit ratio has still to be identified. This review summarizes the current and promising treatment options and their implications for future research and clinical practice.

Synchronized expressions of hepatic stellate cells and their transactivation and liver regeneration during liver injury in an animal model of cholestasis

BACKGROUND

There is much known about hepatic stellate cells (HSCs) during liver injury. However, some aspects remain unclear, such as the natural expression levels of HSCs during the days to weeks after liver injury. Does liver regeneration start the same time as the injury process?

METHODS

Fifty-four male Wistar rats aged 7 to 8 weeks, weighing 200 to 320 g each were subjected to bile duct ligation (BDL). After surgery, they were killed at different times post-BDL. Collagen deposition was analyzed, and immunohistochemical staining of α-smooth muscle actin (α-SMA), vimentin, matrix metalloproteinase-2 (MMP-2), tissue inhibitor matrix metalloproteinase-1, and proliferating cell nuclear antigen antibody (PCNA) was performed to evaluate HSCs and liver regeneration.

RESULTS

The expression of α-SMA was seen as early as day 3 post-BDL, which started from peribiliary to perisinusoidal, and was seen throughout the whole liver sections on day 28 post-BDL. Similar expression patterns were seen in MMP-2 staining. The PCNA expression was strongest around the perisinusoidal area. These expression patterns were not observed in the sham-operated rats.

CONCLUSIONS

The activation of HSCs showed a synchronized fibrogenic process and liver regeneration from days to weeks after liver injury. Matrix degradation was thus found to increase in accordance with chronic liver injury, which thus led to an excessive collagen deposition.

Specific delivery of kinase inhibitors in nonmalignant and malignant diseases

INTRODUCTION

Kinase inhibitors have been hailed as a breakthrough in the treatment of cancer. Extensive research is now being devoted to the development of kinase inhibitors as a treatment for many nonmalignant diseases. However, the use of kinase inhibitors in both malignant and nonmalignant diseases is also associated with side effects and the development of resistance. It may be worthwhile to explore whether cell-specific delivery of kinase inhibitors improves therapeutic efficacy and reduces side effects.

AREAS COVERED

This review aims to provide an overview of the preclinical studies performed to examine the specific targeting of kinase inhibitors in vitro and in vivo. It gives an introduction to kinase signaling pathways induced during disease, along with the possible problems associated with their inhibition. It also discusses the studies on specific delivery and shows that altering the specificity of kinase inhibitors by targeting methods improves their effectivity and safety.

EXPERT OPINION

Compared with the delivery of cytotoxic compounds, the specific delivery of kinase inhibitors has not yet been studied extensively. The studies discussed in this review provide an insight into methods used to target kinase inhibitors to different organs. The targeting of different kinase inhibitors has improved their therapeutic possibilities, but many questions still remain to be studied.

Novel biomarker candidates to predict hepatic fibrosis in hepatitis C identified by serum proteomics

BACKGROUND

Liver biopsy remains the gold standard to assess hepatic fibrosis. It is desirable to predict hepatic fibrosis without the need for invasive liver biopsy. Proteomic techniques allow unbiased assessment of proteins and might be useful to identify proteins related to hepatic fibrosis.

AIMS

We utilized two different proteomic methods to identify serum proteins as candidate biomarkers to predict hepatic fibrosis stage in patients with chronic hepatitis C virus (HCV) infection.

METHODS

Serum was obtained from 24 people with chronic HCV at time of liver biopsy and from 6 normals. Liver biopsy fibrosis was staged 1-4 (Batts-Ludwig). Pooled serum samples (six in each of four fibrosis groups and controls) were analyzed with 4- and 8-plex isobaric tags for relative and absolute quantitation (iTRAQ), determining protein identification (ID) and ratios of relative protein abundance. Nonpooled samples were analyzed with two-dimensional (2-D) gels and difference in gel electrophoresis (DIGE) comparing different samples on the same gel and across gels. Spots varying among groups were measured with densitometry, excised, digested, and submitted for tandem mass spectrometry (MS/MS) protein ID.

RESULTS

iTRAQ identified 305 proteins (minimum 99% ID confidence); 66 were increased or decreased compared with controls. Some proteins were increased or decreased for specific fibrosis scores. From 704 DIGE protein spots, 66 were chosen, 41 excised, and 135 proteins identified, since one gel spot often identified more than one protein.

CONCLUSIONS

Both proteomic methods identified two proteins as biomarker candidates for predicting hepatic fibrosis: complement C4-A and inter-alpha-trypsin inhibitor heavy chain H4.

S-Nitroso-N-acetylcysteine induces de-differentiation of activated hepatic stellate cells and promotes antifibrotic effects in vitro

Nitric oxide (NO) has been shown to act as a potent antifibrogenic agent by decreasing myofibroblast differentiation. S-Nitroso-N-acetylcysteine (SNAC), a NO donor, attenuates liver fibrosis in rats, but the cellular and molecular mechanisms on liver myofibroblast-like phenotype still remain unknown. Here, we investigate the antifibrotic effects of SNAC on hepatic stellate cells, the major fibrogenic cell type in the liver. A murine GRX cell line was incubated with SNAC (100μM) or vehicle (control group) for 72h. Cell viability was measured by MTT colorimetric assay and the conversion of myofibroblast into quiescent fat-storing cell phenotype was evaluated by Oil-Red-O staining. TGFβ-1, TIMP-1, and MMP-13 levels were measure in the supernatant by ELISA. Profibrogenic- and fibrolytic-related gene expression was quantified using real-time qPCR. SNAC induced phenotype conversion of myofibroblast-like phenotype into quiescent cells. SNAC decreased gene and protein expression of TGFβ-1 and MMP-2 compared to control groups. Besides, SNAC down-regulated profibrogenic molecules and up-regulated MMP-13 gene expression, which plays a key role in the degradation of interstitial collagen in liver fibrosis. In conclusion, these findings demonstrate that SNAC efficiently can modulate the activation and functionality of murine hepatic stellate cells and could be considered as an antifibrotic treatment to human liver fibrosis.

Macrophage migration inhibitory factor (MIF) exerts antifibrotic effects in experimental liver fibrosis via CD74

Macrophage migration inhibitory factor (MIF) is a pleiotropic inflammatory cytokine that has been implicated in various inflammatory diseases. Chronic inflammation is a mainstay of liver fibrosis, a leading cause of morbidity worldwide, but the role of MIF in liver scarring has not yet been elucidated. Here we have uncovered an unexpected antifibrotic role for MIF. Mice genetically deleted in Mif (Mif(-/-)) showed strongly increased fibrosis in two models of chronic liver injury. Pronounced liver fibrosis in Mif(-/-) mice was associated with alterations in fibrosis-relevant genes, but not by a changed intrahepatic immune cell infiltration. Next, a direct impact of MIF on hepatic stellate cells (HSC) was assessed in vitro. Although MIF alone had only marginal effects on HSCs, it markedly inhibited PDGF-induced migration and proliferation of these cells. The inhibitory effects of MIF were mediated by CD74, which we detected as the most abundant known MIF receptor on HSCs. MIF promoted the phosphorylation of AMP-activated protein kinase (AMPK) in a CD74-dependent manner and, in turn, inhibition of AMPK reversed the inhibition of PDGF-induced HSC activation by MIF. The pivotal role of CD74 in MIF-mediated antifibrotic properties was further supported by augmented liver scarring of Cd74(-/-) mice. Moreover, mice treated with recombinant MIF displayed a reduced fibrogenic response in vivo. In conclusion, we describe a previously unexplored antifibrotic function of MIF that is mediated by the CD74/AMPK signaling pathway in HSCs. The results imply MIF and CD74 as targets for treatment of liver diseases.

Correlation between hyporesponsiveness to Toll-like receptor ligands and liver dysfunction in patients with chronic hepatitis C virus infection

Hepatitis C virus (HCV)-associated antigens, such as the core and nonstructural antigens, activate host innate immune systems via Toll-like receptors (TLRs). We previously showed that chronic exposure to the core antigen induces hyporesponsiveness to TLR ligands in antigen-presenting cells via activation of TLR2 and that stimulation with TLR ligands results in impaired IL-6 production by peripheral blood monocytes from HCV-infected patients. In the present study, peripheral blood mononuclear cells (PBMCs) isolated from patients with chronic HCV or hepatitis B virus (HBV) infection were stimulated with TLR ligands to determine the production of IL-6 and IL-8 and to identify the clinical parameters associated with hyporesponsiveness to TLR ligands in patients with chronic HCV infection. The results showed that pro-inflammatory cytokine responses to TLR ligands were suppressed in PBMCs isolated from HCV-infected, but not HBV-infected, patients. The reduced cytokine responses to TLR ligands seen in HCV-infected patients correlated with platelet counts and serum prothrombin time levels. In contrast, there was no correlation between TLR-induced cytokine responses and serum levels of core antigen. Thus, hyporesponsiveness to TLR ligands in HCV-infected patients is correlated with liver dysfunction. In conclusion, both host factors and viral factors may be involved in the generation of hyporesponsiveness to TLR ligands in patients with chronic HCV infection.

Etiology and Viral Genotype in Patients with End-Stage Liver Diseases admitted to a Hepatology Unit in Colombia

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the principal risk factor associated to end-stage liver diseases in the world. A study was carried out on end-stage liver disease cases admitted to an important hepatology unit in Medellin, the second largest city in Colombia. From 131 patients recruited in this prospective study, 71% of cases were diagnosed as cirrhosis, 12.2% as HCC, and 16.8% as cirrhosis and HCC. Regarding the risk factors of these patients, alcohol consumption was the most frequent (37.4%), followed by viral etiology (17.6%). Blood and/or hepatic tissue samples from patients with serological markers for HCV or HBV infection were characterized; on the basis of the phylogenetic analysis of HCV 5' UTR and HBV S gene, isolates belonged to HCV/1 and HBV/F3, respectively. These results confirm the presence of strains associated with poor clinical outcome, in patients with liver disease in Colombia; additionally, HBV basal core promoter double mutant was identified in HCC cases. Here we show the first study of cirrhosis and/or HCC in Colombian and HBV and HCV molecular characterization of these patients. Viral aetiology was not the main risk factor in this cohort but alcohol consumption.

Hedgehog signaling antagonist promotes regression of both liver fibrosis and hepatocellular carcinoma in a murine model of primary liver cancer

OBJECTIVE

Chronic fibrosing liver injury is a major risk factor for hepatocarcinogenesis in humans. Mice with targeted deletion of Mdr2 (the murine ortholog of MDR3) develop chronic fibrosing liver injury. Hepatocellular carcinoma (HCC) emerges spontaneously in such mice by 50-60 weeks of age, providing a model of fibrosis-associated hepatocarcinogenesis. We used Mdr2(-/-) mice to investigate the hypothesis that activation of the hedgehog (Hh) signaling pathway promotes development of both liver fibrosis and HCC.

METHODS

Hepatic injury and fibrosis, Hh pathway activation, and liver progenitor populations were compared in Mdr2(-/-) mice and age-matched wild type controls. A dose finding experiment with the Hh signaling antagonist GDC-0449 was performed to optimize Hh pathway inhibition. Mice were then treated with GDC-0449 or vehicle for 9 days, and effects on liver fibrosis and tumor burden were assessed by immunohistochemistry, qRT-PCR, Western blot, and magnetic resonance imaging.

RESULTS

Unlike controls, Mdr2(-/-) mice consistently expressed Hh ligands and progressively accumulated Hh-responsive liver myofibroblasts and progenitors with age. Treatment of aged Mdr2-deficient mice with GDC-0449 significantly inhibited hepatic Hh activity, decreased liver myofibroblasts and progenitors, reduced liver fibrosis, promoted regression of intra-hepatic HCCs, and decreased the number of metastatic HCC without increasing mortality.

CONCLUSIONS

Hh pathway activation promotes liver fibrosis and hepatocarcinogenesis, and inhibiting Hh signaling safely reverses both processes even when fibrosis and HCC are advanced.

Role of integrins in fibrosing liver diseases

Integrins and other cell adhesion molecules regulate numerous physiological and pathological mechanisms by mediating the interaction between cells and their extracellular environment. Although the significance of integrins in the evolution and progression of certain cancers is well recognized, their involvement in nonmalignant processes, such as organ fibrosis or inflammation, is only beginning to emerge. However, accumulating evidence points to an instrumental role of integrin-mediated signaling in a variety of chronic and acute noncancerous diseases, particularly of the liver.

Noninvasive tools to assess hepatic fibrosis: ready for prime time?

Often regarded as the gold standard for fibrosis assessment, liver biopsy carries associated risks; however, it is less than ideal. The need for noninvasive assessment of hepatic fibrosis for disease staging, prognosis, progression, and treatment response is clear. Advances in serologic testing and conventional imaging techniques have reduced the need for liver biopsy. Areas of research include defining cutoff values for specific diseases, further head-to-head comparisons of noninvasive modalities, examination of algorithms using both serum markers and imaging, and the cost-effectiveness of these various tests for diagnostic as well as screening purposes.

Aquaporin-1 promotes angiogenesis, fibrosis, and portal hypertension through mechanisms dependent on osmotically sensitive microRNAs

Changes in hepatic vasculature accompany fibrogenesis, and targeting angiogenic molecules often attenuates fibrosis in animals. Aquaporin-1 (AQP1) is a water channel, overexpressed in cirrhosis, that promotes angiogenesis by enhancing endothelial invasion. The effect of AQP1 on fibrogenesis in vivo and the mechanisms driving AQP1 expression during cirrhosis remain unclear. The purpose of this study was to test the effect of AQP1 deletion in cirrhosis and explore mechanisms regulating AQP1. After bile duct ligation, wild-type mice overexpress AQP1 that colocalizes with vascular markers and sites of robust angiogenesis. AQP1 knockout mice demonstrated reduced angiogenesis compared with wild-type mice, as evidenced by immunostaining and endothelial invasion/proliferation in vitro. Fibrosis and portal hypertension were attenuated based on immunostaining, portal pressure, and spleen/body weight ratio. AQP1 protein, but not mRNA, was induced by hyperosmolality in vitro, suggesting post-transcriptional regulation. Endothelial cells from normal or cirrhotic mice were screened for microRNA (miR) expression using an array and a quantitative PCR. miR-666 and miR-708 targeted AQP1 mRNA and were decreased in cirrhosis and in cells exposed to hyperosmolality, suggesting that these miRs mediate osmolar changes via AQP1. Binding of the miRs to the untranslated region of AQP1 was assessed using luciferase assays. In conclusion, AQP1 promotes angiogenesis, fibrosis, and portal hypertension after bile duct ligation and is regulated by osmotically sensitive miRs.

Peptide-modified albumin carrier explored as a novel strategy for a cell-specific delivery of interferon gamma to treat liver fibrosis

Excessive accumulation of the extracellular matrix proteins primarily produced by activated hepatic stellate cells (HSC) leads to liver fibrosis. To date, no successful therapeutic intervention is available for the treatment of this disease. Platelet derived growth factor beta receptor (PDGFβR) is highly upregulated on disease-inducing activated HSC and thus can be used for delivery of antifibrotic drugs to increase therapeutic efficacy with reduced adverse effects. Interferon gamma (IFNγ) has been recognized as a potent antifibrotic cytokine; however, poor pharmacokinetics and side effects due to frequent administration have limited its clinical use. For HSC-specific delivery, a PDGFβR-specific drug delivery carrier (PPB-HSA) was developed by modifying albumin with PDGFβR-recognizing cyclic peptides. Subsequently, IFNγ was conjugated to PPB-HSA via bifunctional PEG linkers to synthesize PPB-HSA-PEG-IFNγ. In vitro, PPB-HSA-PEG-IFNγ retained complete biological activity similar to unmodified IFNγ and showed PDGFβR-specific binding to human HSC and primary culture-activated rat HSC. In TGFβ-stimulated mouse fibroblasts and human HSC, PPB-HSA-PEG-IFNγ induced significant reduction in crucial fibrotic parameters. In vivo, the conjugate rapidly accumulated into PDGFβR-expressing HSC in fibrotic livers and activated IFNγ-mediated pstat1α signaling pathway. Furthermore, in a CCl(4)-induced acute liver injury model in mice, treatment with HSC-targeted IFNγ strongly ameliorated hepatic fibrogenesis by inducing significant reduction (about 60%; p < 0.01) in collagen I and α-SMA expression as well as enhanced fibrolysis (increased MMP/TIMP ratio; p < 0.05) while free unmodified IFNγ was ineffective. Furthermore, in contrast to free native IFNγ, the conjugate did not induce macrophage infiltration and IL-1β expression in the liver. In conclusion, these data demonstrate the enhanced antifibrotic efficacy and reduced off-target effects of PPB-HSA-PEG-IFNγ conjugate showing the potential of cell-specific targeting of IFNγ for the treatment of liver fibrosis.

Novel engineered targeted interferon-gamma blocks hepatic fibrogenesis in mice

Liver fibrogenesis is a process tightly controlled by endogenous anti- and pro-fibrogenic factors. Interferon gamma (IFNγ) is a potent antifibrogenic cytokine in vitro and might therefore represent a powerful therapeutic entity. However, its poor pharmacokinetics and adverse effects, due to the presence of IFNγ receptors on nearly all cells, prevented its clinical application so far. We hypothesized that delivery of IFNγ specifically to the disease-inducing cells and concurrently avoiding its binding to nontarget cells might increase therapeutic efficacy and avoid side effects. We conjugated IFNγ to a cyclic peptide recognizing the platelet-derived growth factor beta receptor (PDGFβR) which is strongly up-regulated on activated hepatic stellate cells (HSC), the key effector cells responsible for hepatic fibrogenesis. The IFNγ conjugates were analyzed in vitro for PDGFβR-specific binding and biological effects and in vivo in acute (early) and chronic (progressive and established) carbon-tetrachloride-induced liver fibrosis in mice. The targeted-IFNγ construct showed PDGFβR-specific binding to fibroblasts and HSC and inhibited their activation in vitro. In vivo, the targeted-IFNγ construct attenuated local HSC activation in an acute liver injury model. In the established liver fibrosis model, it not only strongly inhibited fibrogenesis but also induced fibrolysis. In contrast, nontargeted IFNγ was ineffective in both models. Moreover, in contrast to unmodified IFNγ, our engineered targeted-IFNγ did not induce IFNγ-related side effects such as systemic inflammation, hyperthermia, elevated plasma triglyceride levels, and neurotropic effects.

CONCLUSION

This study presents a novel HSC-targeted engineered-IFNγ, which in contrast to systemic IFNγ, blocked liver fibrogenesis and is devoid of side effects, by specifically acting on the key pathogenic cells within the liver.

A semiphysiological population model for prediction of the pharmacokinetics of drugs under liver and renal disease conditions

The application of model-based drug development in special populations becomes increasingly important for clinical trial optimization, mostly by providing a rationale for dose selection and thereby aiding risk-benefit assessment. In this article, a semiphysiological approach is presented, enabling the extrapolation of the pharmacokinetics from healthy subjects to patients with different disease conditions. This semiphysiological approach was applied to solifenacin, using clinical data on total and free plasma and urine concentrations in healthy subjects. The analysis was performed using nonlinear mixed-effects modeling and relied on the use of a general partitioning framework to account for binding to plasma proteins and to nonplasma tissues together with principles from physiology that apply to the main pharmacokinetic process, i.e., bioavailability, distribution, and elimination. Application of these physiology principles allowed quantification of the impact of key physiological parameters (i.e., body composition, glomerular function, liver enzyme capacity, and liver blood flow) on the pharmacokinetics of solifenacin. The prediction of the time course of the drug concentration in liver- and renal-impaired patients only required adjustment of the physiological parameters that are known to change upon liver and renal dysfunction without modifying the pharmacokinetic model structure and/or its respective parameter estimates. Visual predictive checks showed that the approach applied was able to adequately predict the pharmacokinetics of solifenacin in liver- and renal-impaired patients. In addition, better insight into the pharmacokinetic properties of solifenacin was obtained. In conclusion, the proposed semiphysiological approach is attractive for prediction of altered pharmacokinetics of compounds influenced by liver and renal disease conditions.

Serum chemokine receptor CXCR3 ligands are associated with progression, organ dysfunction and complications of chronic liver diseases

BACKGROUND

Chemokines are chemotactic mediators that are implicated in liver diseases. In viral hepatitis and primary biliary cirrhosis, a predominant chemokine receptor expressed in the liver is CXCR3, suggesting that its specific ligands are important in the progression of chronic liver diseases across different aetiologies.

METHODOLOGY/PRINCIPAL FINDINGS

We analysed the serum concentrations of the CXCR3 ligands, CXCL9 (monokine induced by interferon-γ), CXCL10 (interferon-γ-inducible protein 10) and CXCL11 (interferon-inducible T cell α chemo-attractant) in healthy controls (n=53), subjects with histologically determined liver fibrosis (n=109) and patients with different stages of cirrhosis (n=153) of various disease aetiologies. Chemokine concentrations were determined by cytometric bead assay or ELISA respectively. Serum concentrations of all three chemokines were significantly increased in patients with chronic liver diseases compared with healthy controls (P<0.001). In the biopsied fibrosis cohort, CXCL9 and CXCL10 were positively associated with the severity of liver fibrosis (histology and serum markers), while CXCL11 was not. In cirrhotic patients, CXCL9 was increased in early Child-Pugh stages, while CXCL11 was elevated only in Child B and C patients and CXCL10 across all stages. Notably, CXCR3 chemokines were also associated with the development of clinical complications of cirrhosis, especially portal hypertension. All chemokines significantly correlated with serum levels of the hepatoprotective cytokines interleukin (IL)-6 and IL-10, suggesting their involvement in a counter-regulatory response during the progression of liver disease, shedding new light on their involvement in the pathophysiology of chronic liver diseases.

CONCLUSIONS

CXCR3 chemokines are differentially expressed during chronic liver diseases across different disease stages and aetiologies. Their association with portal hypertension and hepatoprotective cytokines implies biological functions beyond immune cell recruitment, thereby provoking new diagnostic and therapeutic concepts.

Interleukin-8 is activated in patients with chronic liver diseases and associated with hepatic macrophage accumulation in human liver fibrosis

BACKGROUND

Interleukin-8 (IL-8, CXCL8) is a potent chemoattractant for neutrophils and contributes to acute liver inflammation. Much less is known about IL-8 in chronic liver diseases (CLD), but elevated levels were reported from alcoholic and hepatitis C-related CLD. We investigated the regulation of IL-8, its receptors CXCR1 and CXCR2 and possible IL-8 responding cells in CLD patients.

METHODOLOGY

Serum IL-8 levels were measured in CLD patients (n = 200) and healthy controls (n = 141). Intrahepatic IL-8, CXCR1 and CXCR2 gene expression was quantified from liver samples (n = 41), alongside immunohistochemical neutrophil (MPO) and macrophage (CD68) stainings. CXCR1 and CXCR2 expression was analyzed on purified monocytes from patients (n = 111) and controls (n = 31). In vitro analyses explored IL-8 secretion by different leukocyte subsets.

PRINCIPAL FINDINGS

IL-8 serum levels were significantly increased in CLD patients, especially in end-stage cirrhosis. Interestingly, patients with cholestatic diseases exhibited highest IL-8 serum concentrations. IL-8 correlated with liver function, inflammatory cytokines and non-invasive fibrosis markers. Intrahepatically, IL-8 and CXCR1 expression were strongly up-regulated. However, intrahepatic IL-8 could only be associated to neutrophil infiltration in patients with primary biliary cirrhosis (PBC). In non-cholestatic cirrhosis, increased IL-8 and CXCR1 levels were associated with hepatic macrophage accumulation. In line, CXCR1, but not CXCR2 or CXCR3, expression was increased on circulating monocytes from cirrhotic patients. Moreover, monocyte-derived macrophages from CLD patients, especially the non-classical CD16⁺ subtype, displayed enhanced IL-8 secretion in vitro.

CONCLUSIONS

IL-8 is strongly activated in CLD, thus likely contributing to hepatic inflammation. Our study suggests a novel role of IL-8 for recruitment and activation of hepatic macrophages via CXCR1 in human liver cirrhosis.

Laparoscopic splenectomy is an effective and safe intervention for hypersplenism secondary to liver cirrhosis

BACKGROUND

Laparoscopic splenectomy has become the standard procedure for the normal to moderately enlarged spleens. We performed this study to investigate the safety, feasibility, and effectiveness of laparoscopic splenectomy for hypersplenism secondary to liver cirrhosis.

METHODS

We performed a retrospective chart review of 24 cases of laparoscopic splenectomy (group 1), 24 cases of open splenectomy (group 2) for hypersplenism secondary to liver cirrhosis, and 68 cases of laparoscopic splenectomy for immune thrombocytopenic purpura (group 3). We performed comparisons between groups 1 and 2 and groups 1 and 3 in terms of demographic, intraoperative, postoperative variables, and changes in blood counts and liver function.

RESULTS

Patients in groups 1 and 2 had comparable demographic characteristics, but those in group 1 had less estimated blood loss, fewer complications, and shorter duration of oral intake, and they required less analgesia and shorter post-hospital stays. In both groups, leukocyte and platelet counts increased significantly and transaminase and total bilirubin decreased postoperatively, but not significantly, and there was no significant difference between the two groups. Compared with group 3, patients in group 1 were older, had lower preoperative hemoglobin levels and leukocyte counts, poorer Child-Pugh class, required more operation time, and suffered more estimated blood loss; however, there were no statistically significant differences in terms of conversion rates, transfusion rates, complication rates, and postoperative course.

CONCLUSIONS

Laparoscopic splenectomy is a safe, feasible, and effective procedure for hypersplenism secondary to liver cirrhosis.

PEGylation improves pharmacokinetic profile, liver uptake and efficacy of Interferon gamma in liver fibrosis

Interferon gamma (IFNγ) is a potent cytokine that displays a variety of anti-viral, anti-proliferative, immunomodulatory, apoptotic and anti-fibrotic functions. However, its clinical use is limited to the treatment of few diseases due to the rapid clearance from the body. PEGylated IFN-alpha formulations are shown to be beneficial in viral hepatitis, but PEGylation of IFNγ to enhance its therapeutic effects in liver fibrosis is not yet explored. Liver fibrosis is characterized by the extensive accumulation of an abnormal extracellular matrix and is the major cause of liver-related morbidity and mortality worldwide. To date, there is no pharmacotherapy available for this disease. We modified IFNγ with different-sized linear PEG molecules (5, 10 and 20kDa) and assessed the biological activity in vitro and in vivo. All PEGylated IFNγ constructs were biologically active and activated IFNγ signaling in vitro as determined with a nitric oxide release assay and a pGAS-Luc reporter plasmid assay, respectively. Similar to IFNγ, all PEGylated IFNγ induced a significant reduction of fibrotic parameters in mouse NIH3T3 fibroblasts as shown with immunohistochemical staining and quantitative PCR analyses. In vivo, the pharmacokinetic profile of radiolabeled (125)I-IFNγ-PEG conjugates revealed a decreased renal clearance and an increased plasma half-life with an increase of PEG size. Moreover, the liver accumulation of PEGylated IFNγ constructs was significantly higher than the unmodified IFNγ, which was also confirmed by increased MHC-II expression in the livers. Furthermore, in a CCl(4)-induced acute liver injury model in mice, PEGylated constructs reduced the early fibrotic parameters more drastically than unmodified IFNγ. Of note, these effects were stronger with higher PEG-sized IFNγ constructs. These data nicely correlated with the pharmacokinetic data. In conclusion, PEGylation significantly improved the pharmacokinetics, liver uptake and anti-fibrotic effects of IFNγ. This study opens new opportunities to exploit the therapeutic applications of PEGylated IFNγ for the treatment of liver fibrosis and other diseases.