Metabolic syndrome is associated with severe fibrosis in chronic viral hepatitis and non-alcoholic steatohepatitis

BACKGROUND

The prevalence of metabolic syndrome and its possible impact on the severity of liver histological lesions have not been studied prospectively in chronic liver diseases.

AIM

To investigate the prevalence of metabolic syndrome in patients with chronic viral hepatitis or non-alcoholic steatohepatitis, and to determine its associations with histological severity.

METHODS

We prospectively included 317 patients (hepatitis B e antigen-negative chronic hepatitis B: 95, chronic hepatitis C: 176, non-alcoholic steatohepatitis: 46) with liver biopsy. Metabolic syndrome was defined using the Adult Treatment Panel III criteria. Histological lesions were evaluated according to Ishak's or Brunt's classification.

RESULTS

Metabolic syndrome was present in 10.4% of patients being significantly more prevalent in non-alcoholic steatohepatitis than in chronic viral hepatitis (41.3% vs. 5.1%, P < 0.001). In chronic viral hepatitis, cirrhosis (stages 5-6) was independently associated with increasing age, higher aspartate aminotransferase and gamma-glutamyl-transpeptidase levels, severe necroinflammation and metabolic syndrome (P = 0.016). In non-alcoholic steatohepatitis, severe fibrosis (stages 3-4) was independently associated with severe necroinflammation and metabolic syndrome (P = 0.033). Presence of metabolic syndrome was not associated with presence or severity of steatosis both in chronic viral hepatitis and in non-alcoholic steatohepatitis.

CONCLUSION

Metabolic syndrome is more prevalent in non-alcoholic steatohepatitis than in chronic viral hepatitis; it is associated independently with more severe fibrosis but not with the severity of steatosis, both in chronic viral hepatitis and in non-alcoholic steatohepatitis.

Cellular determinants of hepatitis C virus assembly, maturation, degradation, and secretion

Intracellular infectious hepatitis C virus (HCV) particles display a distinctly higher buoyant density than do secreted virus particles, suggesting that the characteristic low density of extracellular HCV particles is acquired during viral egress. We took advantage of this difference to examine the determinants of assembly, maturation, degradation, and egress of infectious HCV particles. The results demonstrate that HCV assembly and maturation occur in the endoplasmic reticulum (ER) and post-ER compartments, respectively, and that both depend on microsomal transfer protein and apolipoprotein B, in a manner that parallels the formation of very-low-density lipoproteins (VLDL). In addition, they illustrate that only low-density particles are efficiently secreted and that immature particles are actively degraded, in a proteasome-independent manner, in a post-ER compartment of the cell. These results suggest that by coopting the VLDL assembly, maturation, degradation, and secretory machinery of the cell, HCV acquires its hepatocyte tropism and, by mimicry, its tendency to persist.

Body fat distribution and insulin resistance: beyond obesity in nonalcoholic fatty liver disease among overweight men

OBJECTIVE

The aim of this study was to characterize the relationship between nonalcoholic fatty liver disease (NAFLD) and body fat distribution and insulin resistance in a sample of non-diabetic overweight men.

SUBJECTS AND METHODS

We conducted a cross-sectional survey of 117 overweight men with NAFLD, as well as 117 controls, who were matched with regard to age and body mass index. None of the study subjects exhibited signs of alcohol abuse, hepatitis B or C, diabetes or fasting hyperglycemia, or hypertension. The diagnosis of NAFLD was based on dual findings of elevated alanine aminotransferase levels and sonographically-determined fatty liver. Body fat distribution was assessed via bioelectrical impedance. Insulin resistance was evaluated via homeostasis model assessment (HOMA-IR).

RESULTS

The risk of developing NAFLD was found to be profoundly associated with elevated measurements of waist circumference, fat mass, percentage of body fat and abdominal fat, iron, triglycerides, apolipoprotein B, and results of HOMA-IR. Multivariate analysis revealed that NAFLD was significantly associated with elevated measurements of waist circumference, iron, apolipoprotein B, and HOMA-IR.

CONCLUSIONS

Our study provides evidence for a profound and dose-dependent association of NAFLD with central adiposity, insulin resistance in overweight men lacking complications of metabolic syndrome. Overweight subjects with insulin resistance or central adiposity were at more risk of NAFLD than were those subjects with less insulin resistance or central adiposity, even those with a similar degree of obesity.

Apolipoprotein-AII concentrations are associated with liver steatosis in patients with chronic hepatitis C

It has been shown that the hepatitis C virus (HCV) core protein reduces the activity of the microsomal triglyceride transfer protein (MTP) and could lead to steatosis in HCV-infected patients. Experimentally, apolipoprotein-AII (apoAII), which restores triglyceride secretion altered by the HCV core protein, could be protective against HCV steatosis. On the other hand, increasing plasma concentrations of mouse apoAII in transgenic mice produced several aspects of insulin-resistance syndrome, which also is implicated in the pathogenesis of HCV steatosis. This study was designed to investigate the role of apoAII in HCV-related steatosis in humans. Sixty-five hospitalized patients with chronic HCV were included in this study to assess the effects of apoAII, body mass index (BMI), age, insulin sensibility (HOMA), and leptin level on steatosis. Steatosis was observed in 55.3% of patients. Apo-AII was significantly associated with HOMA and with leptin concentrations. In univariate analyses, age, BMI, increased leptin level, increased HOMA, and increased apoAII concentration were associated with steatosis. In multivariate analysis, steatosis was associated with apoAII concentration, age, gender, and BMI. Contrary to previous hypotheses, apoAII is not a protective factor against HCV steatosis but is significantly associated with the development of liver steatosis. The fact that the plasma levels of apoAII correlate with HOMA and leptin levels in HCV-infected patients suggests that apoAII may contribute to hepatic steatosis progression in relationship to visceral obesity, insulin resistance, and metabolism of triglyceride-rich lipoproteins.

Prevalence of elevated alanine aminotransferase among US adolescents and associated factors: NHANES 1999-2004

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is a common cause of liver disease in children and adolescents. The majority of studies of NAFLD in children have been in select populations of the clinically obese. Study aims were to estimate the prevalence of elevated alanine aminotransferase (ALT, as a marker of NAFLD) in a general contemporary adolescent population and to identify leading risk factors for ALT elevation (>30 U/L).

METHODS

We analyzed data of adolescent participants (aged 12-19 years; N = 5586) in the National Health and Nutrition Examination Survey 1999-2004, a representative sample of the civilian noninstitutionalized US population.

RESULTS

The prevalence of elevated ALT levels (>30 U/L) was 7.4% among white adolescents, 11.5% among Mexican American adolescents, and 6.0% among black adolescents. Elevated ALT levels were prevalent in 12.4% of male subjects compared with 3.5% of female subjects. Multivariable associations with elevated ALT levels were found for sex (odds ratio [OR] male vs female, 7.7; 95% confidence interval [CI], 3.9-15.1), ethnicity (OR black vs white, 0.6; 95% CI, 0.3-1.3; OR Mexican American vs white, 1.6; 95% CI, 1.0-2.6), waist circumference (OR per 1 SD, 1.4; 95% CI, 1.0-2.0), and fasting insulin level (OR per 1 SD, 1.6; 95% CI, 1.2-2.1). Age, C-reactive protein levels, and triglyceride levels were also positively and socioeconomic position inversely associated with elevated ALT levels. The magnitude of associations were similar across ethnic groups.

CONCLUSIONS

ALT level is associated with waist circumference and insulin resistance even in a young population. These characteristics could be utilized to identify adolescents who may benefit from screening for NAFLD, offering an opportunity to prevent disease progression at an early age.

Use of insulin sensitizers in NASH

This article briefly discusses nonalcoholic fatty liver disease (NAFLD) and its association with the metabolic syndrome, its pathogenesis and natural history. It then presents a detailed discussion on the efficacy and safety of different insulin sensitizers in patients who have NASH.

Prevalence of elevated alanine aminotransferase among US adolescents and associated factors: NHANES 1999-2004

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is a common cause of liver disease in children and adolescents. The majority of studies of NAFLD in children have been in select populations of the clinically obese. Study aims were to estimate the prevalence of elevated alanine aminotransferase (ALT, as a marker of NAFLD) in a general contemporary adolescent population and to identify leading risk factors for ALT elevation (>30 U/L).

METHODS

We analyzed data of adolescent participants (aged 12-19 years; N = 5586) in the National Health and Nutrition Examination Survey 1999-2004, a representative sample of the civilian noninstitutionalized US population.

RESULTS

The prevalence of elevated ALT levels (>30 U/L) was 7.4% among white adolescents, 11.5% among Mexican American adolescents, and 6.0% among black adolescents. Elevated ALT levels were prevalent in 12.4% of male subjects compared with 3.5% of female subjects. Multivariable associations with elevated ALT levels were found for sex (odds ratio [OR] male vs female, 7.7; 95% confidence interval [CI], 3.9-15.1), ethnicity (OR black vs white, 0.6; 95% CI, 0.3-1.3; OR Mexican American vs white, 1.6; 95% CI, 1.0-2.6), waist circumference (OR per 1 SD, 1.4; 95% CI, 1.0-2.0), and fasting insulin level (OR per 1 SD, 1.6; 95% CI, 1.2-2.1). Age, C-reactive protein levels, and triglyceride levels were also positively and socioeconomic position inversely associated with elevated ALT levels. The magnitude of associations were similar across ethnic groups.

CONCLUSIONS

ALT level is associated with waist circumference and insulin resistance even in a young population. These characteristics could be utilized to identify adolescents who may benefit from screening for NAFLD, offering an opportunity to prevent disease progression at an early age.

A model to estimate insulin sensitivity in dairy cows

Impairment of the insulin regulation of energy metabolism is considered to be an etiologic key component for metabolic disturbances. Methods for studies of insulin sensitivity thus are highly topical. There are clear indications that reduced insulin sensitivity contributes to the metabolic disturbances that occurs especially among obese lactating cows. Direct measurements of insulin sensitivity are laborious and not suitable for epidemiological studies. We have therefore adopted an indirect method originally developed for humans to estimate insulin sensitivity in dairy cows. The method, "Revised Quantitative Insulin Sensitivity Check Index" (RQUICKI) is based on plasma concentrations of glucose, insulin and free fatty acids (FFA) and it generates good and linear correlations with different estimates of insulin sensitivity in human populations. We hypothesized that the RQUICKI method could be used as an index of insulin function in lactating dairy cows. We calculated RQUICKI in 237 apparently healthy dairy cows from 20 commercial herds. All cows included were in their first 15 weeks of lactation. RQUICKI was not affected by the homeorhetic adaptations in energy metabolism that occurred during the first 15 weeks of lactation. In a cohort of 24 experimental cows fed in order to obtain different body condition at parturition RQUICKI was lower in early lactation in cows with a high body condition score suggesting disturbed insulin function in obese cows. The results indicate that RQUICKI might be used to identify lactating cows with disturbed insulin function.

Glucose abnormalities are an independent risk factor for nonresponse to antiviral treatment in chronic hepatitis C

OBJECTIVES

The influence of glucose abnormalities on the efficacy of antiviral treatment is unknown. This study investigated whether glucose abnormalities (impaired fasting glucose and type 2 diabetes) influence the response to antiviral therapy with interferon plus ribavirin in patients with chronic hepatitis C.

METHODS

A total of 178 treatment-naïve patients with chronic hepatitis C treated with combination therapy were retrospectively studied. SVR was assessed after completing treatment. Fasting plasmatic glucose was measured prior to therapy.

RESULTS

Compared with nonresponders (N = 111), patients with SVR (N = 67) had lower plasma glucose (94.1 +/- 12.7 vs 104.4 +/- 25.8 mg/dL, P= 0.001) and a lower prevalence of glucose abnormalities (24.24%vs 44.14%, P= 0.012). The SVR rate was 45.13% in patients with normoglycemia (N = 113), 28.26% in patients with impaired fasting glucose (N = 46), and 15.78% in type 2 diabetic patients (N = 19) (P < 0.001). Multivariate logistic regression identified genotype 1 (OR 1.55, 95% CI 1.01-2.41, P= 0.05), gamma-glutamyltranspeptidase level (OR 6.41, 95% CI 1.86-22.07, P= 0.003), and presence of glucose abnormalities (OR 2.33, 95% CI 1.04-5.20, P= 0.039) as being independently associated with the absence of an SVR. In addition, patients with glucose abnormalities (N = 65) showed a lower virological response rate when compared with a subgroup of normoglycemic patients (N = 65) matched for sex, age, and liver fibrosis (24.6%vs 44.6%, P= 0.001).

CONCLUSIONS

Glucose abnormalities are an independent predictor of poor virological response to combined therapy in hepatitis C virus infected patients.

Risk factors for intrahepatic and extrahepatic cholangiocarcinoma in the United States: a population-based case-control study

BACKGROUND & AIMS

Intrahepatic and extrahepatic cholangiocarcinomas are rare and highly malignant cancers of the bile duct. Although the incidence of extrahepatic cholangiocarcinoma (ECC) has remained constant, the incidence of intrahepatic cholangiocarcinoma (ICC) has increased in the United States. Because the etiology of both tumors is poorly understood, a population-based case-control study was conducted to examine the association of ECC and ICC with preexisting medical conditions.

METHODS

Medical conditions among 535 ICC patients, 549 ECC patients (diagnosed 1993-1999), and 102,782 cancer-free controls were identified by using the Surveillance, Epidemiology and End Results-Medicare databases. Logistic regression analysis was used to calculate adjusted odds ratios.

RESULTS

In addition to established risk factors (choledochal cysts, cholangitis, inflammatory bowel disease), several other conditions were significantly associated with ECC and ICC: biliary cirrhosis (ECC, ICC: P < .001), cholelithiasis (ECC, ICC: P < .001), alcoholic liver disease (ECC, P < .001; ICC, P = .01), nonspecific cirrhosis (ECC, ICC: P < .001), diabetes (ECC, ICC: P < .001), thyrotoxicosis (ECC, P = .006; ICC, P = .04), and chronic pancreatitis (ECC, ICC: P < .001). Conditions only associated with ICC were obesity (ECC, P = .71; ICC, P = .01), chronic nonalcoholic liver disease (ECC, P = .08; ICC, P = .02), HCV infection (ECC, P = .67; ICC, P = .01), and smoking (ECC, P = .07; ICC, P = .04).

CONCLUSIONS

Several novel associations with ECC and ICC were identified. HCV infection, chronic nonalcoholic liver disease, and obesity, all of which are increasing in incidence, and smoking were associated only with ICC, suggesting that these conditions might explain the divergent incidence trends of the tumors.

Hepatic steatosis in chronic hepatitis B develops due to host metabolic factors: a comparative approach with genotype 1 chronic hepatitis C

BACKGROUND/AIMS

Hepatic steatosis has not been adequately studied in chronic hepatitis B, while it is considered to be a cardinal feature in chronic hepatitis C and to be mainly metabolically induced in patients infected with genotype 1. We investigated the prevalence of and the parameters associated with steatosis in HBeAg-negative chronic hepatitis B.

METHODS

We studied 213 patients with HBeAg-negative chronic hepatitis B and compared them with 163 patients with genotype-1 chronic hepatitis C. Steatosis was semi-quantitatively graded.

RESULTS

Steatosis was significantly less frequent in chronic hepatitis B than chronic hepatitis C (60% versus 72%, P=0.016), but there was no difference in the prevalence of moderate/severe steatosis. In chronic hepatitis B, steatosis was associated only with higher body mass index (P=0.002), while moderate/severe steatosis was associated only with higher body mass index (P=0.043) and diabetes (P=0.031). Steatosis was relatively less frequent in chronic hepatitis B than chronic hepatitis C non-diabetic, normal-weight patients (45.6% versus 62.5%, P=0.063), but it did not differ in diabetic and/or overweight/obese patients with chronic hepatitis B or chronic hepatitis C.

CONCLUSIONS

Hepatic steatosis in HBeAg-negative chronic hepatitis B (a) is less frequent than in genotype-1 chronic hepatitis C, (b) is mainly associated with presence of host metabolic factors, such as high body mass index and diabetes and (c) does not seem to be associated with the severity of liver histological lesions.

Pathological study of 130 cases of nonalcoholic fatty liver disease based on NASH-CRN system

To summarize the pathological features of nonalcoholic liver disease (NAFLD) in China based on a histological scoring system for NAFLD designed by the Pathology Committee of NASH Clinical Research Network (NASH-CRN), the specimens of liver needle biopsies from 130 patients with NAFLD were histopathologically analyzed by haematoxylin eosin, reticular fiber and Masson trichrome stain. Immunohistochemistry staining was used to exclude non-NAFLD cases combined with clinical data. Hepatic steatosis, lobular inflammation, hepatocytic ballooning and fibrosis were presented widespread in NAFLD liver tissues. Furthermore, macrovesicular steatosis predominantly located in acinar zone 3 was the main histologic feature of NAFLD and lobular inflammation was usually presented mildly. Hepatocyte ballooning was observed in 94.6% of all 130 cases. Mild perisinusoidal fibrosis and periportal fibrosis were often observed in stage 1 cases. According to the statistic analysis, hepatic steatosis was positively correlated with lobular inflammation, hepatocytic ballooning and fibrosis (r = 0.587, 0.488, 0.374, respectively, all P value < 0.01). The number of microgranulomas, lipogranulomas and apoptotic bodies increased following severity of steatosis, lobular inflammation and fibrosis. Meanwhile, the number of megamitochondria and glycogen nuclei was paralleveled to the degree of hepatocytic ballooning (P value all < 0.01). We suggest that the role of portal inflammation should be emphasized besides hepatic steatosis, lobular inflammation, hepatocyte ballooning and fibrosis in diagnosis and evaluation of NAFLD. It needs to be further verified whether microgranulomas, lipogranulomas and apoptosis bodies could be used as histopathological markers of development of NAFLD. The number of megamitochondria is more frequently be found in NAFLD, while in alcoholic liver diseases was Mallory bodies.

Transient elastography for the assessment of chronic liver disease: Ready for the clinic?

Transient elastography is a recently developed non-invasive technique for the assessment of hepatic fibrosis. The technique has been subject to rigorous evaluation in a number of studies in patients with chronic liver disease of varying aetiology. Transient elastography has been compared with histological assessment of percutaneous liver biopsy, with high sensitivity and specificity for the diagnosis of cirrhosis, and has also been used to assess pre-cirrhotic disease. However, the cut-off values between different histological stages vary substantially in different studies, patient groups and aetiology of liver disease. More recent studies have examined the possible place of transient elastography in clinical practice, including risk stratification for the development of complications of cirrhosis. This review describes the technique of transient elastography and discusses the interpretation of recent studies, emphasizing its applicability in the clinical setting.

Glucocorticoids, metabolism and metabolic diseases

Since the discovery of the beneficial effects of adrenocortical extracts for treating adrenal insufficiency more than 80 years ago, glucocorticoids (GC) and their cognate, intracellular receptor, the glucocorticoid receptor (GR) have been characterized as critical components of the delicate hormonal control system that determines energy homeostasis in mammals. Whereas physiological levels of GCs are required for proper metabolic control, excessive GC action has been tied to a variety of pandemic metabolic diseases, such as type II diabetes and obesity. Highlighted by its importance for human health, the investigation of molecular mechanisms of GC/GR action has become a major focus in biomedical research. In particular, the understanding of tissue-specific functions of the GC-GR pathway has been proven to be of substantial value for the identification of novel therapeutic options in the treatment of severe metabolic disorders. Therefore, this review focuses on the role of the GC-GR axis for metabolic homeostasis and dysregulation, emphasizing tissue-specific functions of GCs in the control of energy metabolism.

Correlation of serum adiponectin levels and hepatic steatosis in hepatitis C virus genotype 1 infection

Steatosis is an important cofactor in hepatitis C virus (HCV) because it is associated with fibrosis and reduces early and sustained virologic response. Recent studies suggest that HCV genotype 1 is not steatogenic if additional risk factors are not present. Because hypoadiponectinemia was found to be a feature of nonalcoholic steatohepatitis (NASH) independent of insulin resistance, its level in patients with hepatitis C genotype can reveal the optimal therapeutic strategy. This study was conducted to determine the role of the relationship between steatosis and serum adiponectin levels in the progression of liver damage in HCV genotype 1 without known risk factors for NASH. Patients (n=50) with biopsy-proven chronic hepatitis C (CHC), positive HCV RNA, and raised alanine aminotransferase were enrolled. They were carefully selected to rule out possible confounding factors for the presence of steatosis and additional systemic or liver disease. Associations between serum adiponectin levels and grade of steatosis, histologic activity index (HAI), fibrosis grade of liver biopsies, patient age, HCV viral load, and serum transaminase activities were studied. Also, adiponectin levels were compared with those of a control group of 30 healthy volunteers with normal ultrasound findings of the upper abdomen who had no known NASH risk factors. The investigators found that adiponectin levels in patients with CHC genotype 1 were similar to those in healthy subjects. No significant association was found between adiponectin levels and severity of steatosis, HCV RNA levels, HAI, transaminases, and fibrosis. Steatosis was present in 41 patients (82%) with CHC. Multivariate analysis of data on 50 patients revealed that severity of steatosis was independently related to age alone (P=.03). A correlation between HCV RNA load and HAI was observed (P=.02; r=0.712). HAI also was associated with stage of fibrosis (P=.00; r= 0.612). In cases of chronic HCV genotype 1 hepatitis, steatosis is a common histologic feature, although no risk factors are known. Results presented here cannot establish an association between adiponectin and severity of steatosis when risk factors for steatosis are unknown. Additional studies are needed to discover a metabolic treatment that would seek to improve the progression of hepatic steatosis in CHC infection.

Gamma-glutamyltransferase activity and development of the metabolic syndrome (International Diabetes Federation Definition) in middle-aged men and women: Data from the Epidemiological Study on the Insulin Resistance Syndrome (DESIR) cohort

OBJECTIVE

Among hepatic enzymes, gamma-glutamyltransferase (GGT) is the main predictor of type 2 diabetes incidence, although it has not been shown that GGT predicts pre-diabetes states. Our aim was to study the association of GGT with the development of the metabolic syndrome (MetS).

RESEARCH DESIGN AND METHODS

We analyzed the 3-year data from the Data from Epidemiological Study on the Insulin Resistance Syndrome prospective cohort of 1,656 men and 1,889 women without MetS at baseline, according to the International Diabetes Federation definition.

RESULTS

Over 3 years, 309 participants developed the MetS. After adjustment for age, alcohol intake, physical activity, smoking habits, and alanine aminotransferase (ALT), the odds ratios for incident MetS increased across baseline GGT quartiles (1, 1.96, 2.25, and 3.81 in men, P < 0.03; and 1, 1.23, 1.80, and 1.58 in women, P < 0.05). After additional adjustment for insulin resistance markers (fasting insulin or homeostasis model assessment of insulin resistance index), the association was attenuated and the linear relation no longer significant in both sexes (P = 0.08, P = 0.16). However, men in the highest in comparison to the lowest quartile of GGT retained a significant risk for incident MetS. In women, there was no longer a significant risk. GGT was significantly associated with the 3-year incidence of individual components of the MetS. The incidence of the MetS also increased with ALT, but after adjustment on GGT this association remained significant only in women.

CONCLUSIONS

GGT, a predictor of type 2 diabetes, was associated with a risk of incident MetS. This association was mainly related with insulin resistance but was independent of other confounding factors.

Proteomic profiling of human liver biopsies: hepatitis C virus-induced fibrosis and mitochondrial dysfunction

Liver biopsies from hepatitis C virus (HCV)-infected patients offer the unique opportunity to study human liver biology and disease in vivo. However, the low protein yields associated with these small samples present a significant challenge for proteomic analysis. In this study we describe the application of an ultrasensitive proteomics platform for performing robust quantitative proteomic studies on microgram amounts of HCV-infected human liver tissue from 15 patients at different stages of fibrosis. A high-quality liver protein database containing 5,920 unique protein identifications supported high throughput quantitative studies using (16)O/(18)O stable isotope labeling in combination with the accurate mass and time (AMT) tag approach. A total of 1,641 liver biopsy proteins were quantified, and analysis of variance (ANOVA) identified 210 proteins exhibiting statistically significant differences associated with fibrosis stage. Hierarchical clustering showed that biopsies representative of later fibrosis stages (for example, Batts-Ludwig stages 3-4) exhibited a distinct protein expression profile, indicating an apparent down-regulation of many proteins when compared with samples from earlier fibrosis stages (for example, Batts-Ludwig stages 0-2). Functional analysis of these signature proteins suggests that impairment of key mitochondrial processes including fatty acid oxidation and oxidative phosphorylation, and response to oxidative stress and reactive oxygen species occurs during advanced stage 3 to 4 fibrosis.

CONCLUSION

The results reported here represent a significant advancement in clinical proteomics providing to our knowledge, the first demonstration of global proteomic alterations accompanying liver disease progression in patients chronically infected with HCV. Our findings contribute to a generally emerging theme associating oxidative stress and hepatic mitochondrial dysfunction with HCV pathogenesis.

Nitrosative stress predicts the presence and severity of nonalcoholic fatty liver at different stages of the development of insulin resistance and metabolic syndrome: possible role of vitamin A intake

BACKGROUND

Although nonalcoholic fatty liver disease (NAFLD) is associated with the metabolic syndrome, the mechanisms responsible for the development of NAFLD at different stages of the development of insulin resistance are unknown. Diet, adipokines, and nitrosative stress have been linked to both NAFLD and insulin resistance.

OBJECTIVE

We aimed to identify the factors that are specifically associated with NAFLD at different stages in the development of insulin resistance and the metabolic syndrome.

DESIGN

Circulating concentrations of adipokines (ie, tumor necrosis factor-alpha, adiponectin, resistin, leptin, and interleukin-6), markers of nitrosative stress (nitrotyrosine), dietary habits, and MTP -493G/T polymorphism were cross-sectionally related to the presence and severity of insulin resistance (homeostasis model assessment index for insulin resistance: >or=2), the metabolic syndrome, and fatty liver in 64 nonobese nondiabetic patients with NAFLD (33 insulin-sensitive and 31 insulin-resistant subjects) and 74 control subjects without liver disease who were matched for sex, BMI, homeostasis model assessment index for insulin resistance status, and the various features of the metabolic syndrome.

RESULTS

Persons with NAFLD had greater systemic nitrosative stress and a lower intake of vitamins A and E than did control subjects, but the 2 groups did not differ significantly in any other features. Nitrotyrosine and adiponectin concentrations and vitamin A intakes independently predicted alanine aminotransferase concentrations in NAFLD patients and liver histology in a subgroup of 29 subjects with biopsy-proven nonalcoholic steatohepatitis.

CONCLUSIONS

Oxidative stress is operating in NAFLD and nonalcoholic steatohepatitis, even in the absence of insulin resistance, the metabolic syndrome, and hypoadiponectinemia, which aggravate liver histology at more severe stages of metabolic disease. The possible pathogenetic role of reduced vitamin A intake in NAFLD warrants further investigation.

Efficacy of zinc administration in patients with hepatitis C virus-related chronic liver disease

OBJECTIVE

Zinc supplementation has been shown to contribute to inhibition of liver fibrosis and improvement in hepatic encephalopathy. However, little is known about the anti-inflammatory effect of zinc on hepatitis C virus (HCV)-related chronic liver disease (CLD). We therefore examined the effects of zinc administration on inflammatory activity and fibrosis in the liver of patients with HCV-related CLD.

MATERIAL AND METHODS

Polaprezinc, a complex of zinc and l-carnosine, was administrated at 225 mg/day for 6 months to 14 patients with HCV-related CLD, in addition to their ongoing prescriptions. Peripheral blood cell counts, liver-related biochemical parameters, serological markers for liver fibrosis, HCV-RNA loads, and serum levels of zinc and ferritin were evaluated before and after zinc administration.

RESULTS

Serum zinc concentrations were positively correlated with hepatic reserve before zinc supplementation. A significant increase in serum zinc level was observed after zinc supplementation (64+/-15 versus 78+/-26 mg/dl, p=0.0156). Treatment with polaprezinc significantly decreased serum aminotransferase levels (aspartate aminotransferase (AST): 92+/-33 versus 63+/-23 IU/l, p=0.0004; alanine aminotransferase (ALT): 106+/-43 versus 65+/-32 IU/l, p=0.0002), whereas alkaline phosphatase levels were significantly increased (305+/-117 versus 337+/-118 U/l, p=0.0020). Serum ferritin levels were significantly decreased by treatment with polaprezinc (158+/-141 versus 101+/-80 ng/ml, p=0.0117). The reduction rate of ALT levels by polaprezinc was positively correlated with that of ferritin (r(2)=0.536, p=0.0389). There was a tendency toward a decrease in serum type IV collagen 7S levels after treatment with polaprezinc. However, administration of polaprezinc did not affect peripheral blood cell counts, other liver function tests, or HCV-RNA loads.

CONCLUSIONS

These findings suggest that polaprezinc exerts an anti-inflammatory effect on the liver in patients with HCV-related CLD by reducing iron overload.

The effect of a silybin-vitamin e-phospholipid complex on nonalcoholic fatty liver disease: a pilot study

Oxidative stress leads to chronic liver damage. Silybin has been conjugated with vitamin E and phospholipids to improve its antioxidant activity. Eighty-five patients were divided into 2 groups: those affected by nonalcoholic fatty liver disease (group A) and those with HCV-related chronic hepatitis associated with nonalcoholic fatty liver disease (group B), nonresponders to treatment. The treatment consisted of silybin/vitamin E/phospholipids. After treatment, group A showed a significant reduction in ultrasonographic scores for liver steatosis. Liver enzyme levels, hyperinsulinemia, and indexes of liver fibrosis showed an improvement in treated individuals. A significant correlation among indexes of fibrosis, body mass index, insulinemia, plasma levels of transforming growth factor-beta, tumor necrosis factor-alpha, degree of steatosis, and gamma-glutamyl transpeptidase was observed. Our data suggest that silybin conjugated with vitamin E and phospholipids could be used as a complementary approach to the treatment of patients with chronic liver damage.

HCV infection facilitates asymptomatic carotid atherosclerosis: preliminary report of HCV RNA localization in human carotid plaques

BACKGROUND

Clinical and experimental evidence suggests that hepatitis C virus (HCV) infection shows peculiar characteristics that strongly support a role in the development of atherosclerosis. We aimed to investigate whether (a) HCV infection can facilitate asymptomatic carotid lesions and (b) the presence of HCV RNA sequences can be shown in plaque tissues.

METHODS

The status of carotid arteries, studied as intima-media thickness (IMT) in carotid bifurcation and prevalence and severity of plaques in internal carotid artery, was investigated by high-resolution B-mode ultrasonography in 31 HCV seropositive (HCV+) and in 120 age-matched HCV seronegative (HCV-) subjects evaluated for cardiovascular risk factors. The atherosclerotic risk profile, inflammation markers and main liver function tests were also studied in all patients. HCV RNA sequences were investigated by highly sensitive reverse transcriptase-polymerase chain reaction (RT-PCR) in plaque tissues and serum of 2 HCV+ patients who underwent carotid revascularization.

RESULTS

Genomic and antigenomic HCV RNA strands were evidenced within both the carotid plaque tissues examined. The prevalence of an IMT > 1 mm, but not the prevalence and severity of internal carotid plaques, was significantly higher (P < 0.001) in HCV+ than in HCV patients. The atherosclerotic risk profile for traditional and inflammatory factors did not differ between the HCV+ and HCV- groups. Main liver function tests did not differ between the two groups. HCV positivity was significantly associated with >1 mm IMT (P < 0.01) according to univariate analysis, and this association remained significant in multivariate regression analysis.

CONCLUSIONS

The novel finding of HCV RNA sequences within carotid plaques suggests a local pro-atherogenetic action of the virus inside the plaque. On the whole our data strongly support that HCV infection facilitates the occurrence of carotid atherosclerotic lesions.

Microarray analyses and molecular profiling of steatosis induction in immortalized human hepatocytes

Hepatic steatosis is an important risk factor for the development of inflammation, fibrosis and impaired liver regeneration. The factors regulating lipid accumulation and driving hepatic steatosis toward inflammation, fibrosis and impaired regeneration are largely unknown. The aim of this study was to identify major alterations in gene expression occurring in steatotic hepatocytes, and to analyze how these changes impact cellular processes associated with steatosis. Microarray gene chips and RT-PCR were performed to analyze changes in gene expression induced in fatty human immortalized hepatocytes after treatment with 50 muM oleic acid for 7 days. Lipid metabolism and triglyceride accumulation in these cells was examined by Oil-Red-O staining, thin-layer chromatography (TLC) and immunofluorescence. Caspase 3 activity, BrdU incorporation and trypan blue exclusion were used to study apoptosis, proliferation and cell viability. Finally, quantitative analysis of signalling induced by insulin was performed by Western blot. Characterization of steatosis in three hepatocyte-derived cell lines indicated that the immortalized human hepatocytes (IHH) line was the most appropriate cell line for this study. Gene expression analysis showed significant alterations in the transcription of two major classes of genes involved either in cholesterol and fatty acid biosynthesis, as well as lipid export, or in apoptosis and cell proliferation. Such changes were functionally relevant, since TLC indicated that synthesis and accumulation of triglycerides were increased in steatotic cells, while synthesis of cholesterol and fatty acids were decreased. Lipid accumulation in IHH was associated with an increased apoptosis and an inhibition of cell proliferation and viability. No detectable changes in genes associated with insulin resistance were observed in steatotic cells, but signalling induced by insulin was more efficient in steatotic IHH as compared to control cells. We conclude that IHH represent a new valuable model of steatosis, not associated with insulin resistance, to study at both the genetic and functional level factors involved in the process of lipid accumulation and steatosis-associated liver injury.

Metabolic and cardiovascular risk profiles and hepatitis C virus infection in rural Egypt

BACKGROUND AND AIMS

To investigate the relationship between lipid profiles and diabetes with past and chronic hepatitis C virus (HCV) infection among village residents of Egypt.

PATIENTS AND METHODS

Fasting lipids and glucose profiles were compared among adults never infected with HCV (negative HCV antibodies), infected in the past (positive HCV antibodies and negative HCV RNA) and chronically infected (positive HCV antibodies and HCV RNA).

RESULTS

Of the 765 participants, 456 (59.6%) were female, and median age was 40 (range 25-88) years. Chronic HCV infection was present in 113 (14.8%) and past infection in 67 (8.8%). After adjustment for age and sex, participants with chronic HCV infection had lower plasma low density lipoproteins (LDL) cholesterol and triglyceride levels compared with those never infected (age and sex adjusted differences (95% CI) were -19.0 (-26.3 to -11.7) mg/dl and -26.2 (-39.0 to -13.3) mg/dl, respectively). In contrast, participants with cleared HCV infection had higher triglyceride levels compared with those never infected (age and sex adjusted difference (95% CI) was +16.0 (0.03 to 31.9) mg/dl). In multivariate analysis, participants with chronic HCV infection were more likely to have diabetes (OR 3.05, 95% CI 1.19 to 7.81) compared with those never infected, independent of LDL cholesterol levels.

CONCLUSION

In conclusion, this community based study has shown that in a single population, chronic HCV infection is associated with glucose intolerance and, despite that, a favourable lipid pattern. An intriguing finding was the high triglyceride levels observed among participants with past infection, suggesting that elevated triglycerides at the time of acute infection may facilitate viral clearance.

Glucose intolerance and hypoadiponectinemia are already present in lean patients with chronic hepatitis C infected with genotype non-3 viruses

OBJECTIVES

Steatosis and metabolic abnormalities seem to be frequent and deleterious in chronic hepatitis C. Changes in glucose homeostasis and in adiponectin levels, an adipokine with anti-inflammatory and insulin-sensitive properties, were evaluated in patients with chronic hepatitis C according to steatosis, liver fibrosis and body mass index.

METHODS

Seventy-three patients with chronic hepatitis C (40 men, 33 women) infected with genotypes non-3 and 22 healthy controls (11 men and 11 women) were included in the study and all had a biochemical evaluation, including metabolic parameters, adiponectin measurement, and a liver biopsy. Insulin sensitivity was assessed with the HOMA 1-IR insulin resistance model.

RESULTS

Steatosis was found in 65.7% of the patients and significant fibrosis (METAVIR F2-F4) was present in 28.7%. The presence of steatosis could only be predicted by fibrosis, whereas significant fibrosis could be predicted by steatosis and age. Adiponectin levels were significantly decreased (-32%) with the severity of the steatosis. Although overweight chronic hepatitis C patients (body mass index>or=25 kg/m2) had insulin resistance and hypoadiponectinemia, lean chronic hepatitis C patients (body mass index<25 kg/m2) had already significantly higher glycemia and lower adiponectin levels than in controls.

CONCLUSIONS

This study confirms the high incidence of steatosis in patients infected by hepatitis C virus genotypes non-3, well linked to the development of fibrosis and metabolic abnormalities. Importantly, the present findings put emphasis on the early development of these metabolic abnormalities as they were already found in lean patients with chronic hepatitis C. The direct implication of hepatitis C virus is thus further stressed in the development of steatosis and insulin resistance, with or without involvement of host factors.

HCV and diabetes. A two-question-based reappraisal

We used available studies to answer two clinically relevant questions, i.e. whether those with type 2 diabetes should undergo hepatitis C virus screening and whether hepatitis C virus positive individuals should be screened for diabetes. Four reasons argue against the hypothesis of screening diabetics for hepatitis C virus. First, although it induces insulin resistance, hepatitis C virus is not directly diabetogenic. Second, the clinical phenotype of hepatitis C virus-associated type 2 diabetes might be a clue to target the specific diabetic population to be screened. Third, diabetic patients are expected to be poor responders to antivirals and evidence that this might result in recovery from type 2 diabetes is insufficient. Fourth, no econometric data are available in the specific subset of those with type 2 diabetes. Case finding of type 2 diabetes in those with hepatitis C virus infection, in contrast, might be considered in those patients with type 2 diabetes who have cirrhosis, in whom--due to increased prevalence and severity of hepatic encephalopathy--diabetes is associated with increased mortality. Preliminary evidence suggests that the prognosis of cirrhosis might benefit from improved glycemic control and thus from earlier diagnosis of type 2 diabetes. Finally, studies are needed to ascertain the most cost-effective strategy of case-finding type 2 diabetes among those who are hepatitis C virus-infected. In conclusion, available data enabled us to answer the two questions. Hepatitis C virus screening should best be restricted to those (lean) diabetic patients with (advanced) liver disease. Glucose tolerance testing should best be performed in those with hepatitis C virus-related cirrhosis. However, additional studies are needed to support the cost-effectiveness of our conclusions.

Increased liver mast cell recruitment in patients with chronic C virus-related hepatitis and histologically documented steatosis

Hepatitis C virus (HCV) is still one of the major causes of chronic viral infection worldwide, and hepatic steatosis is a frequent pathological finding in patients with chronic HCV-related diseases. It is unclear whether the steatosis is associated with host factors or the virus itself, although a consistent relationship has been found between steatosis and a necro-inflammatory reaction with the increased secretion of immuno-regulators. A primary sources of inflammatory mediators are mast cells (MCs) bone marrow-derived cells that are detected in both normal and diseased livers. We determined MC density and correlated it with the fibrosis, inflammatory reaction and steatosis observed in the liver biopsies of patients affected by HCV with or without steatosis. All the histological features were assessed using a computer-aided image analysis system. There was a statistically significant difference in MC density between the HCV-infected patients with and without steatosis, with the lower mean value being detected in those without (P < 0.02). Furthermore, a nonstatistically significant difference in fibrosis and inflammation between the two patient groups was found. In conclusion, this is the first study showing a significant increase in MC density in the tissues of patients with chronic HCV infection and histologically documented steatosis.

Subcutaneous vitamin E ameliorates liver injury in an in vivo model of steatocholestasis

Several genetic metabolic liver diseases share the pathological features of combined steatosis and cholestasis, or steatocholestasis. The aims of this study were to develop and characterize an in vivo model for steatocholestasis and to evaluate the effects of an antioxidant treatment on liver injury, oxidative stress, and mitochondrial perturbations in this model. Obese and lean Zucker rats received intravenous (IV) injections of glycochenodeoxycholic acid (GCDC) and were killed 4 hours later. Liver enzymes were measured; the liver histology was assessed, and hepatic mitochondria were analyzed for mitochondrial lipid peroxidation. In separate experiments, rats received daily injections of subcutaneous (SQ) vitamin E before GCDC infusion. Bile acid-induced injury (serum AST and ALT and liver histology) was more severe in the obese rats than in the lean rats, characterized predominantly by extensive cell necrosis with minimal evidence of apoptosis. SQ vitamin E provided significant protection against IV GCDC-induced hepatic injury, in vitro GCDC-induced permeability transition, and cytochrome C and apoptosis-inducing factor release from isolated mitochondria.

CONCLUSION

Steatosis sensitizes the liver to bile acid-induced necrotic hepatocyte injury, which is responsive to vitamin E therapy.

Very low density lipoprotein and low density lipoprotein isolated from patients with hepatitis C infection induce altered cellular lipid metabolism

Several abnormalities of lipid metabolism, including hypo-beta-lipoproteinemia and liver steatosis are associated with infection by hepatitis C virus (HCV). The aim of this study was to determine whether circulating lipoproteins of patients with HCV infection could directly cause alterations of lipid cellular metabolism. To this end the metabolic response of human monocyte-derived macrophages (HMDM) to very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL), measuring the cholesteryl ester (CE) and triglyceride (TG) production was analyzed. Lipoproteins were isolated from 18 patients infected with hepatitis C virus (HCV-VLDL and HCV-LDL) and from normal healthy donors (ct-VLDL and ct-LDL). In comparison to ct-lipoproteins, HCV-lipoproteins induced significant differences in HMDM CE and TG production. HCV-VLDL decreased CE and TG production; while HCV-LDL induced an increased TG synthesis. The present findings suggest that HCV infection modifies VLDL and LDL molecular composition, affecting cellular lipid metabolism, thus promoting intracellular lipid accumulation and hypo-beta-lipoproteinemia.

The multifaceted associations of hepatobiliary disease and diabetes

OBJECTIVE

To investigate the association of diabetes and hepatobiliary disease.

METHODS

We performed a MEDLINE search of the English-language literature published between January 1980 and January 2007 for studies in which diabetes was associated with liver diseases.

RESULTS

Through its association with the insulin resistance syndrome, type 2 diabetes is associated with nonalcoholic fatty liver disease, nonalcoholic steatohepatitis (NASH), NASH-cirrhosis, and NASH-cirrhosis-related hepatocellular carcinoma. Because of the association with insulin resistance, insulin sensitizers may slow or even arrest the progress of these diseases. Type 2 but not type 1 diabetes is associated with hepatitis C virus but not hepatitis B viral infection. This association is likely due to hepatitis C viral infection of the pancreatic beta-cells. Early detection and antiviral therapy can decelerate the development of diabetes. Type 1 diabetes is associated with hemochromatosis and autoimmune hepatitis. Because of the presence of autonomic neuropathy, cholelithiasis but not cholecystitis is more common in patients with diabetes than in the general population. Therefore, asymptomatic cholelithiasis in patients with diabetes no longer warrants a cholecystectomy. In patients with advanced liver disease of any cause, insulin resistance and diabetes have an increased frequency of occurrence and can be reversed with liver transplantation. Rarely, medications used to treat type 2 diabetes have been associated with drug-induced hepatitis.

CONCLUSION

The prevalence of hepatobiliary diseases is increased in patients with diabetes. Early recognition and treatment of these conditions can prevent, stabilize, or even reverse hepatic damage and prevent the development of hepatic carcinoma and liver failure.

Ultrasound diagnosis of fatty liver in patients with chronic liver disease: a retrospective observational study

OBJECTIVES

Hepatic ultrasound (US) is readily available and physicians usually trust the results of an US report suggesting fatty liver, but there are conflicting reports on its accuracy, especially in patients with chronic liver disease (CLD). Therefore, we retrospectively examined liver biopsies in patients with CLD and compared the histologic results to the hepatic US findings.

METHODS

Liver biopsies were graded for fat (grades 0 to 3), inflammation (grades 0 to 4), and fibrosis (stages 0 to 4) in 131 patients with CLD (89% had chronic hepatitis C). Hepatic US interpretations were grouped into 3 categories-"normal," "fatty liver," and "nonspecific." A secondary analysis was performed using 3 sonographic categories based on the echogenicity: normal, "increased echogenicity," and "heterogenous." The US results were then compared with the liver biopsy results.

RESULTS

A normal US report was associated with many false negatives, as 25% of these patients had fat (grades 1 to 3) on biopsy; furthermore, 46% had "significant fibrosis" (stages 2 to 4) or "significant inflammation" (grades 2 to 4). A "fatty liver" interpretation correctly identified fat on biopsy in 36.4% and "significant fat" (grades 2 to 3) in 11.4%, but 66% had significant fibrosis or significant inflammation. An US with increased echogenicity correctly identified fat in 43.5% and significant fat in 19.4%, but 69.4% had significant fibrosis or significant inflammation. The sensitivity of an US ranged from 11.4% to 88.2% and the specificity ranged from 40.4% to 86.2%, depending on the degree of steatosis on biopsy and the sonographic interpretation being considered.

CONCLUSIONS

US is inaccurate for diagnosing hepatic steatosis in patients with CLD. Echogenic abnormalities are more likely to be the result of fibrosis or inflammation in this setting.

Differences and similarities in early atherosclerosis between patients with non-alcoholic steatohepatitis and chronic hepatitis B and C

BACKGROUND/AIMS

To compare carotid intima-media thickness (IMT) - an index of early atherosclerosis - among patients with non-alcoholic steatohepatitis (NASH), patients with chronic hepatitis B (HBV) or C (HCV) and control subjects.

METHODS

We studied 60 consecutive patients with biopsy-proven NASH, 60 patients with HCV, 35 patients with HBV, and 60 healthy controls who were comparable for age and sex. Common carotid IMT was measured with ultrasonography in all participants by a single operator blinded to subjects' characteristics.

RESULTS

Carotid IMT measurements were markedly different among the groups; the lowest values were in controls, intermediate in patients with HBV or HCV, and highest in those with NASH (0.84+/-0.1 vs. 0.97+/-0.1 vs. 1.09+/-0.2 vs. 1.23+/-0.2mm, respectively; p<0.001). The marked differences in carotid IMT that were observed among the groups were little affected by adjustment for age, sex, body mass index, smoking, LDL cholesterol, insulin resistance (by homeostasis model assessment) and components of the Adult Treatment Panel III-defined metabolic syndrome. Concordantly, in logistic regression analysis, NASH, HBV and HCV predicted carotid IMT independent of potential confounders.

CONCLUSIONS

These data suggest that NASH, HCV and HBV are strongly associated with early atherosclerosis independent of classical risk factors, insulin resistance and metabolic syndrome components.

De novo nonalcoholic fatty liver disease after liver transplantation

Hepatic steatosis is a recognized problem in patients after orthotopic liver transplant (OLT). However, de novo development of nonalcoholic fatty liver disease (NAFLD) has not been well described. The aim of this study was to determine the prevalence and predictors of de novo NAFLD after OLT. A retrospective analysis was performed on 68 OLT patients with donor liver biopsies and posttransplantation liver biopsies. Individual medical charts were reviewed for demographics, indication for OLT, serial histology reports, genotypes for hepatitis C, comorbid conditions, and medications. Liver biopsies were reviewed blindly and graded according to the Brunt Scoring System. Multivariate logistic regression analysis was used to study the risk factors for developing NAFLD. The interval time from OLT to subsequent follow-up liver biopsy was 28 +/- 18 months. A total of 12 patients (18%) developed de novo NAFLD, and 6 (9%) developed de novo NASH. The regression model indicated that the use of angiotensin-converting enzyme inhibitors (ACE-I) was associated with a reduced risk of developing NAFLD after OLT (odds ratio, 0.09; 95% confidence interval, 0.010-0.92; P = 0.042). Increase in body mass index (BMI) of greater than 10% after OLT was associated with a higher risk of developing NAFLD (odds ratio, 19.38; 95% confidence interval, 3.50-107.40; P = 0.001). In conclusion, de novo NAFLD is common in the post-OLT setting, with a significant association with weight gain after transplant. The use of an ACE-I may reduce the risk of developing post-OLT NAFLD.

Impact of non-alcoholic fatty liver disease on chronic hepatitis B

BACKGROUND

The impact of superimposed non-alcoholic fatty liver disease (NAFLD) is well established in patients with chronic hepatitis C (CH-C), but the impact in patients with chronic hepatitis B (CH-B) is less clear.

AIM

This study aims to evaluate the prevalence of NAFLD in patients with CH-B and the association with viral and host factors, particularly in patients with metabolic syndrome (MS).

DESIGN

Data from patients with CH-B was obtained from our databases. Patients with excessive alcohol use were excluded. Hepatitis B virus (HBV) genotyping by INNO-LIPA was available for some patients. The presence of MS was defined according to the Adult Treatment Panel III (ATP III). All biopsies were read by two hepatopathologists using Metavir, modified histologic activity index (MHAI), as well as a NAFLD pathologic protocol. Patients were classified as (1) those without NAFLD; (2) those with simple hepatic steatosis; (3) and those with superimposed non-alcoholic steatohepatitis (NASH). Factors associated with superimposed NAFLD, its subtypes, and hepatic fibrosis were also analysed.

RESULTS

Subjects included 153 HBV patients [66% male, age 50.5+/-27.5 years, body mass index 24.7+/-3.7 kg/m(2), waist 83.2+/-10.9 cm; 8.5% Caucasian, 67% Asian, aspartate aminotransferase (AST) 63.2+/-88.2 IU/l, alanine aminotransferase (ALT) 98.6+/-164.6 IU/l, glucose 111.6+/-50.5 mg/dl, HBV-DNA 1.8 x 10(8)+/-1.9 x 10(6) copies/ml, 7% with MS, 13% with diabetes, 20% with arterial hypertension and 8.5% with dyslipidaemia]. Liver biopsy was available for 64 subjects [19% had superimposed NAFLD, 13% had superimposed NASH, 86% had some degree of fibrosis, and 39% had advanced fibrosis (Ishak >3)]. Patients with HBV and superimposed NASH were significantly older (55 vs. 42 years, P=0.008), more likely to have hypertension (63% vs. 15%, P=0.006) and dyslipidaemia (50% vs. 8%, P=0.006), and had a larger waist circumference (92 vs. 83 cm, P=0.03). The presence of fibrosis was associated with higher waist circumference (84 vs. 80 cm, P=0.03), higher HBV-DNA (1.9 x 10(8) vs. 5 x 10(6) copies/ml, P=0.005), and elevated ALT >40 IU/l (73.6% vs. 33.3%, P=0.02).

CONCLUSIONS

The components of MS (obesity, hypertension, and dyslipidaemia) are associated with the presence of NASH in patients with CH-B. The presence of hepatic fibrosis seems to be associated with known host and viral factors as well as the presence of abdominal obesity.

Has natural selection in human populations produced two types of metabolic syndrome (with and without fatty liver)?

Fatty liver is closely related to the development of the insulin resistance syndrome that largely results from abnormal insulin signaling in three major organs: (i) skeletal muscle in which insulin sensitivity depends on fat content and metabolic activity (exercise); (ii) adipose tissue, which serves as a reservoir of energy in the form of triglycerides; and (iii) the liver, which variably serves as a source or storage site of carbohydrates and lipids. In many respects, the fatty liver resembles a mixture of brown adipose tissue (microvesicular steatosis) and white adipose tissue (macrovesicular steatosis) including the stages of fatty droplet accumulation, and the expression of uncoupling proteins and perilipin-like substances. Furthermore, the development of an inflammatory infiltrate and the increased production of cytokines as occurs in adipose tissue, suggest that the liver in some individuals serves as an extension of adipose tissue. Moreover, current evidence indicates that these morphological changes represent altered gene expression similar to that of adipocytes. However, fatty liver does not appear to be a uniform feature of the metabolic syndrome and there is substantial variation in humans in the development of fatty liver independent of insulin resistance. In this regard, the variable development of fatty liver in Palmipedes (migratory fowl) and its close relationship to skeletal muscle utilization of fatty acids, lipoprotein metabolism and thermoregulation are instructive. The predilection to non-alcoholic fatty liver disease among some varieties of Palmipedes suggests that the development of fatty liver represents an adaptive process, closely integrated with skeletal muscle fat utilization and adipose tissue distribution, and facilitates survival in a very cold, resource-scarce environment. Variation in human populations with metabolic syndrome likewise suggests that the trait evolved in populations exposed in ancient times to different environmental challenges and, because the liver plays a central role in lipid metabolism, the presence or absence of fatty liver is likely to be integrated with insulin sensitivity in other target organs and with lipoprotein metabolism.

Early initiation of antiretroviral therapy: the current best way to reduce liver-related deaths in HIV/hepatitis C virus-coinfected patients

Approximately 25% to 35% of HIV-infected persons in developed countries are coinfected with hepatitis C virus (HCV). HCV liver disease is accelerated by HIV coinfection, especially at low CD4 cell counts. Highly active antiretroviral therapy (HAART) dramatically reduces HIV-related mortality, and liver disease has emerged as a major cause of death in HIV/HCV-coinfected persons. Anti-HCV therapy with pegylated interferon plus ribavirin can cure HCV infection in up to 40% of coinfected patients; however, only approximately 10% of coinfected patients are considered candidates. Hence, HCV therapy cures approximately 4% of coinfected patients. Eleven cohort studies have shown that HAART is associated with a reduced rate of progression of HCV liver disease, and 4 of these studies have demonstrated a reduction in liver-related mortality. Although offering HCV therapy to the few eligible HIV/HCV-coinfected patients is important, early initiation of HAART in coinfected patients has a greater public health impact in reducing liver-related mortality than in curing HCV infection in approximately 4% of these patients.

The impact of insulin resistance, serum adipocytokines and visceral obesity on steatosis and fibrosis in patients with chronic hepatitis C

AIMS

To assess whether host metabolic factors influence the degree of hepatic steatosis and fibrosis in patients infected with hepatitis C virus, and to evaluate the impact of anti-viral therapy on insulin resistance and serum levels of adipocytokines.

METHODS

Clinical and biochemical features, anthropometrical characteristics, and levels of fasting insulin, leptin, adiponectin and resistin were measured in 'naïve' patients with chronic hepatitis C, before, during and after therapy with Peg-Interferon-alpha 2a plus Ribavirin.

RESULTS

Forty-eight patients were included (M/F 28/20; mean age 50.0 +/- 12.6 years; 62.5% genotype-1). Body mass index was 26.4 +/- 4.0 kg/m(2), and visceral obesity was present in 24 patients. At multivariate analysis (RR; 95% CI), steatosis was associated to older age (1.08; 1-1.18), necroinflammatory activity (17.67; 1.6-194.46), and raised insulin levels (1.39; 1.1-1.77). Fibrosis was related to necroinflammatory activity (25.73; 2.54-261.11), and steatosis (6.47; 1.09-38.29). Sustained viral response was achieved by 62.5% of patients and was associated with younger age (0.92; 0.85-0.99), genotype non-1 (10.61; 1.52-73.76) and absence of visceral obesity (13.78; 2.36-80.29). At the end of follow-up, insulin and the homeostasis model assessment for insulin resistance were reduced and adiponectin increased when compared with baseline, all unrelated to the outcome of treatment.

CONCLUSIONS

Visceral obesity correlates with the degree of steatosis and fibrosis, and it negatively affects treatment response. Significant changes of insulin resistance and adipocytokines occur under treatment, irrespective of virological outcome.

A growing burden: the pathogenesis, investigation and management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common hepatic disorder in western countries, and its incidence is increasing. This review outlines the significant health burden posed by NAFLD and discusses what is presently known about its pathogenesis, including the roles of the metabolic syndrome, obesity, insulin resistance, hepatic steatosis, reactive oxygen species, inflammatory cytokines and adipocytokines. The way in which NAFLD is clinically diagnosed is described, and areas of uncertainty surrounding its investigation are identified, before discussing the relative merits of the limited treatment options available and looking ahead to potential therapeutic strategies for the future.

Detection of auto-antibodies against cytochrome P4502E1 (CYP2E1) in chronic hepatitis C

BACKGROUND/AIMS

Chronic hepatitis C (CHC) is often associated with auto-immune reactions. In the light of the role of alcohol in promoting CHC progression, we have investigated the possible presence of auto-reactivity against the ethanol-inducible cytochrome P4502E1 (CYP2E1) in CHC patients with and without alcohol consumption.

METHODS

The IgG reactivity against recombinant human CYP2E1 was evaluated by solid-phase immunoassays in 102 CHC patients with different alcohol consumption and 59 HCV-free controls.

RESULTS

Auto-antibodies against CYP2E1 were significantly (p<0.0001) increased in CHC patients as compared to controls. Anti-CYP2E1 IgG above the 97th percentile in the controls were evident in 41 (40%) CHC patients. Competition experiments revealed that CYP2E1 recognition was not due to the cross-reactivity with CYP2D6. The detection of anti-CYP2E1 IgG was unrelated to alcohol consumption and no difference in gender, age, aminotransferase levels and virus genotype was evident among the patients with or without anti-CYP2E1 auto-antibodies. However, anti-CYP2E1 auto-reactivity was significantly (p=0.025) associated with the severity of periportal/periseptal interface hepatitis. Moreover, confocal microscopy demonstrated that anti-CYP2E1 IgG associated with CHC recognized CYP2E1 exposed on the outer side of hepatocyte plasma membranes.

CONCLUSIONS

HCV infection favours the breaking of self-tolerance against CYP2E1 that might contribute to hepatocyte injury.

Evaluation of serum biomarkers of fibrosis and injury in Egyptian patients with chronic hepatitis C

BACKGROUND/AIMS

We evaluated whether surrogate serum biomarkers for liver injury are comparable to liver biopsy in Egyptian patients with hepatitis C virus (HCV) infection.

SUBJECTS

Two hundred and twenty Egyptian patients, 91% infected with genotype-4 HCV, undergoing liver biopsy during evaluation for interferon/ribavirin therapy.

METHODS

Liver biopsy scored by the Ishak method was compared to biochemical tests, platelet count and two fibrosis biomarkers: hyaluronic acid (HA) and YKL-40. Univariate and logistic regression analyses determined independent predictors of fibrotic, inflammatory, and fatty changes. Biomarkers were evaluated for ability to differentiate between severe fibrosis/cirrhosis and no/mild fibrosis.

RESULTS

Although increasing age, HA, YKL-40, AST, reduced platelet count, and AST and HA/platelet count ratios were associated with fibrosis by univariate analysis, the other variables were not significant after controlling for HA (p=0.0001) and age (p=0.004). Although age and some biomarkers were associated with inflammation, none remained significant after controlling for fibrosis. YKL-40 (p=0.04) and aspartate aminotransferase (p=0.05) remained associated with steatosis after controlling for fibrosis.

CONCLUSIONS

In Egyptians with chronic HCV, young patients with low levels of HA are at very low risk of fibrosis. This can limit the number of liver biopsies to those whose clinical findings conflict with the biomarker results.

Evaluating Liver Fibrosis Progression and the Impact of Antiretroviral Therapy in HIV and Hepatitis C Coinfection Using a Noninvasive Marker

The effects of highly active antiretroviral therapy (HAART) on progression of hepatic fibrosis in hepatitis C virus (HCV) coinfection with HIV are not well understood and are difficult to measure because of the need for repeated liver biopsy. We evaluated the evolution of a noninvasive measure of liver fibrosis, the alanine aspartyl transferase (AST)-to-platelet ratio index (APRI), longitudinally and determined its predictive value for hepatic outcomes in HIV-positive patients with and without HCV coinfection. A total of 673 HIV-positive patients without liver complications at baseline (540 with HIV only, 133 with HIV-HCV coinfection) were followed between 1991 and 2004 for a median of 4.6 years (3524 person-years). At baseline, HIV-HCV coinfection had a higher median APRI compared with HIV infection alone (0.59 vs. 0.33; P < 0.0001). The natural logarithm of the APRI [ln(APRI)] changed significantly over time, particularly among patients with HIV-HCV coinfection. The baseline ln(APRI) was predictive of liver complications (hazard ratio [HR] = 4.0, 95% confidence interval [CI]: 2.5 to 6.4 per log), as was HCV (HR = 4.5, 95% CI: 1.5 to 14). Cumulative HAART did not protect against liver complications, although it was significantly associated with progression of APRI scores in HIV-HCV coinfection and in HIV alone. In conclusion, the APRI may be a useful marker for longitudinal evaluation of the progression of liver disease in HIV-HCV coinfection.

Sonographic fatty liver and hepatitis B virus carrier status: Synergistic effect on liver damage in Taiwanese adults

AIM: To examine the epidemiology of hepatitis B virus carrier status (HBVC) and sonographic fatty liver (SFL) in Taiwanese adults, and to evaluate their possible interaction in inducing liver damage (LD). From an epidemiological viewpoint, we analyzed previous studies which indicated that fatty liver sensitizes host immune response to HBV infection and enhances liver damage.

METHODS: A cross-sectional retrospective analysis of health records including medical history, physical examination, abdominal sonogram, blood biochemistry and hepatic virological tests. We utilized the Student’s t-test, chi-square, multivariate logistic regression and synergy index to assess risks for LD.

RESULTS: Among a total of 5406 Taiwanese adults (mean age 46.2 years, 51.5% males), the prevalence of LD, HBVC and SFL were 12.3%, 15.1% and 33.4%, respectively; 5.1% of participants had SFL plus HBVC. Multivariate logistic regression analysis demonstrated that male gender (odds ratio (OR) = 2.8, 95% confidence interval (CI): 2.3-3.5), overweight state (OR = 1.6, 95% CI: 1.3-2.0), HBVC (OR = 2.5, 95% CI: 2.0-3.1) and SFL (OR = 4.2, 95% CI: 2.2-5.3) were independently associated with LD. Synergism analysis showed that the adjusted OR for LD in adults with HBVC-alone was 3.3 (95% CI: 2.4-4.6), SFL-alone, 4.7 (95% CI: 3.7-6.1) and combined HBVC and SFL, 9.5 (95% CI: 6.8-13.3); the synergy index was 1.4 (95% CI: 1.001-2.0).

CONCLUSION: In Taiwanese adults, SFL plus HBVC have a significant synergistic association with LD.

Hepatic steatosis in genotype 4 chronic hepatitis C is mainly because of metabolic factors

BACKGROUND/AIM

Hepatic steatosis is considered to be mostly associated with viral factors in genotype 3 and metabolic factors in genotype 1 chronic hepatitis C, while there are rather few data for genotype 4. We determined the parameters associated with steatosis in 350 chronic hepatitis C patients, focusing on genotype 4.

METHODS

Histological lesions were evaluated according to Ishak's classification and steatosis was semiquantitatively graded. Several patient characteristics on the biopsy day were also evaluated.

RESULTS

Steatosis was present in 73% of patients without significant differences among genotypes. Moderate/severe steatosis was more frequent in genotype 3 than 4 (44% vs 26%, P= 0.025) and similar between genotype 4 and 1 patients. Moderate/severe steatosis was associated with body mass index (BMI) in genotype 4 (P= 0.023) and gamma-glutamyl-transpeptidase in genotype 3 patients (P= 0.044). In 150 nondiabetic patients with BMI < or =25 kg/m(2), moderate/severe steatosis was present in 15, 40, and 11% of genotype 1, 3, and 4 patients, respectively, (P= 0.005) and was independently associated only with genotype 3. In multivariate analysis, steatosis grade or moderate/severe steatosis was independently associated with higher BMI, genotype 3, and lower cholesterol.

CONCLUSIONS

Moderate or severe steatosis is significantly less frequent in genotype 4 than 3 chronic hepatitis C patients and similar between genotype 4 and 1. In nondiabetic, nonoverweight patients, moderate or severe steatosis is present in only 10-15% of genotype 4 or 1 compared with 40% of genotype 3 patients. Thus, hepatic steatosis in genotype 4 is mostly associated with metabolic factors, similar to those in genotype 1.

Obesity management

Because obesity is associated with an increased risk of multiple health problems, it is important for gastroenterologists and all health care providers routinely to identify, evaluate, and treat patients for obesity in the course of daily practice. Therapy for obesity always begins with lifestyle management and may include pharmacotherapy or surgery. Setting an initial weight loss goal of 10% over 6 months is a realistic target, followed by long-term management.

Steatosis as a cofactor in other liver diseases: hepatitis C virus, alcohol, hemochromatosis, and others

As obesity prevalence rises, there is evidence that fatty liver disease can act synergistically with other chronic liver diseases to aggravate parenchymal injury. This is characterized best in chronic hepatitis C, where steatosis is caused by viral and metabolic effects. There is evidence that steatosis and its metabolic abnormalities also exacerbate other diseases, such as alcoholic liver disease, hemochromatosis, and, possibly, drug-induced liver disease. The pathogenesis seems related to increased susceptibility of steatotic hepatocytes to apoptosis, enhanced oxidative injury, and altered hepatocytic regeneration. Data suggest that active management of obesity may improve liver injury and decrease the progression of fibrosis in patients who have other chronic liver diseases.

Metabolic syndrome and NASH

Clinical and epidemiologic studies have associated non-alcoholic fatty liver with the metabolic syndrome, with insulin resistance as the pivotal pathogenic factor. Obesity, type 2 diabetes mellitus, dyslipidemia, and hypertension contribute to risk for liver disease and to disease progression. The presence of multiple metabolic abnormalities is associated with the severity of liver disease. Patients have a high risk for cardiovascular morbidity and mortality, mediated by early atherosclerosis. This evidence has precise therapeutic implications: only a behavioral approach to lifestyle correction will address all alterations characterizing the metabolic syndrome, including metabolic liver disease.

Hepatic steatosis in hepatitis C: comparison of diabetic and nondiabetic patients in the hepatitis C antiviral long-term treatment against cirrhosis trial

BACKGROUND & AIMS

Hepatic steatosis often is observed in patients with chronic hepatitis C and has been reported to be associated with hepatic fibrosis and impaired treatment response in some studies. Our aim was to determine the prevalence of and risk factors for hepatic steatosis among Hepatitis C Antiviral Long-term Treatment against Cirrhosis patients, and to determine the relationship between steatosis, fibrosis, and sustained virologic response (SVR) to re-treatment with pegylated interferon and ribavirin.

METHODS

Baseline data from 1143 Hepatitis C Antiviral Long-term Treatment against Cirrhosis patients, with a mean body mass index of 30, 5% with genotype 3, 38% with cirrhosis, and 24% with diabetes were analyzed.

RESULTS

Steatosis scores of 0, 1, 2, 3, and 4 were observed in 19%, 42%, 30%, 8%, and 1% of patients, respectively. High body mass index, triglyceride and alanine aminotransferase levels, and genotype 3 were associated with higher grades of steatosis. Among nondiabetic patients, steatosis scores of 0-2 but not scores of 3-4 were associated significantly with cirrhosis. For diabetic patients, there was no association between steatosis and cirrhosis. Similarly, steatosis scores of 2-4 were associated with a lack of SVR among nondiabetic but not among diabetic patients.

CONCLUSIONS

In this cohort with predominantly hepatitis C virus genotype 1 infection, steatosis was associated strongly with metabolic factors that contribute to nonalcoholic fatty liver disease. Steatosis correlated with increasing stages of fibrosis up to but not including cirrhosis. Steatosis had a negative impact on SVR among nondiabetic but not diabetic patients. The discordant findings between nondiabetic and diabetic patients indicate that these 2 groups should be considered separately when analyzing metabolic factors and liver disease outcomes.