Insulin resistance is associated with steatosis in nondiabetic patients with genotype 1 chronic hepatitis C

Leptin as a Key Player in Insulin Resistance of Liver Cirrhosis? A Cross-Sectional Study in Liver Transplant Candidates

Insulin resistance is associated with increased risk of death and liver transplantation in the cirrhotic population, independent of disease aetiology. However, factors accounting for insulin resistance in the context of cirrhosis are incompletely understood. This study aimed to investigate the association between adiponectin and leptin with insulin resistance in cirrhotic patients and to assess the influence of disease severity on insulin resistance and metabolic status. This cross-sectional study included 126 non-diabetic cirrhotic transplant candidates. The homeostasis model assessment 2 model was used to determine the insulin resistance index, and fasting adiponectin, leptin, insulin, c-peptide, glucose, HbA1c, and lipid profiles were analysed. Insulin resistance was detected in 83% of subjects and associated with increased leptin, fasting plasma glucose and body mass index, and lower triglyceride levels. Logistic regression analysis identified leptin and triglycerides as independent predictors of insulin resistance (OR 1.247, 95% CI 1.076-1.447, p = 0.003; OR 0.357, 95% CI 0.137-0.917, p = 0.032.). Leptin levels remained unchanged, whereas adiponectin levels increased (p < 0.001) with disease progression, and inversely correlated with HbA1c (ρ = -0.349, p < 0.001). Our results indicate that leptin resistance, as indicated by elevated leptin levels, can be regarded as a contributing factor to insulin resistance in cirrhotic patients, whereas triglycerides elicited a weak protective effect. Progressively increasing adiponectin levels elicited a positive effect on glucose homeostasis, but not insulin sensitivity across disease stages.

Hepatitis C Infection: A Systemic Disease

It is critical to recognize that hepatitis C virus (HCV) infection is, in fact, a multifaceted systemic disease with both hepatic and extrahepatic complications. It is also important to recognize that the comprehensive burden of HCV should include not only its clinical burden but also its burden on the economic and patient-reported outcomes. It is only through this comprehensive approach to HCV infection that we can fully appreciate its true burden and understand the full benefit of curing HCV for the patient and the society.

Hepatitis C infection: A multi-faceted systemic disease with clinical, patient reported and economic consequences

Hepatitis C virus infection (HCV) affects approximately 170-200 million individuals globally. HCV is one of the primary causes of hepatocellular carcinoma (HCC) and cirrhosis and has been identified as the leading indication for liver transplantation in most Western countries. Because HCV is a systemic disease with hepatic, extrahepatic, economic and patient reported consequences, it is important for healthcare practitioners to understand the comprehensive and multi-faceted picture of this disease. In this context, it is important to fully appreciate the impact of HCV on the individual patient and the society. With the recent advent of the new generation of direct antiviral agents, the long standing goal of eradicating HCV in most infected patients has been accomplished. Therefore, now more than ever, it is critical to assess the total benefits of sustained virological response in a comprehensive manner. This should not be limited to the clinical benefits of HCV cure, but also to account for the improvement of patient reported health and economic outcomes of HCV cure. It is only through this comprehensive approach to HCV and its treatment that we will understand the full impact of this disease and the tremendous gains that have been achieved with the new antiviral regimens.

Nomogram for hepatic steatosis: A simple and economical diagnostic tool for massive screening

AIM

To establish a simple economical diagnostic tool for prediction of hepatic steatosis in patients with hepatitis B virus (HBV) infection.

METHODS

From January 2006 to January 2015,a total of 1325 consecutive subjects who underwent liver biopsy were enrolled. According to the results of multivariate logistic regression analysis, a new nomogram was conducted. Then discrimination and calibration were conducted to assess the clinical diagnostic value of nomogram.

RESULTS

The nomogram consisted of age, triglyceride (TG), low-density lipoprotein (LDL), uric acid (UA), haemoglobin (HGB). For prediction of hepatic steatosis, the AUROC of nomogram was 0.792 (95%CI: 0.758-0.826). With cut off value of 0.11, 699 (52.8%) of 1325 patients could be free from liver biopsy with a correct rate of 95.3% for diagnosis of hepatic steatosis.

CONCLUSION

The nomogram for hepatic steatosis has a better clinical diagnostic value for prediction of hepatic steatosis in patients with HBV infection. From the perspective of cost-effectiveness and clinical practice, it is worth considering the use of the nomogram as a mass screening tool before further liver biopsy or imaging examinations.

Substitution in Amino Acid 70 of Hepatitis C Virus Core Protein Changes the Adipokine Profile via Toll-Like Receptor 2/4 Signaling

Background & Aims

It has been suggested that amino acid (aa) substitution at position 70 from arginine (70R) to glutamine (70Q) in the genotype 1b hepatitis C virus (HCV) core protein is associated with insulin resistance and worse prognosis. However, the precise mechanism is still unclear. The aim of this study was to investigate the impact of the substitution at position 70 in HCV core protein on adipokine production by murine and human adipocytes.

Methods

The influence of treatment with HCV core protein (70R or 70Q) on adipokine production by both 3T3-L1 and human adipocytes were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and triglyceride content was also analyzed. The effects of toll-like receptor (TLR)2/4 inhibition on IL-6 production by 3T3-L1 induced by HCV core protein were examined.

Results

IL-6 production was significantly increased and adiponectin production was reduced without a change in triglyceride content by treatment with 70Q compared to 70R core protein in both murine and human adipocytes. IL-6 induction of 3T3-L1 cells treated by 70Q HCV core protein was significantly inhibited with anti-TLR2 antibody by 42%, and by TLR4 inhibitor by 40%.

Conclusions

Our study suggests that extracellular HCV core protein with substitution at position 70 enhanced IL-6 production and reduced adiponectin production from visceral adipose tissue, which can cause insulin resistance, hepatic steatosis, and ultimately development of HCC.

The Mechanism of Interferon Refractoriness During Hepatitis C Virus Infection and Its Reversal with a Peroxisome Proliferator-Activated Receptor α Agonist

Patients who respond poorly to therapies for hepatitis C virus (HCV) infection display a characteristic phenotype with high basal hepatic interferon-stimulated gene (ISG) expression, but limited induction following interferon (IFN) treatment. The molecular pathways that mediate this refractory state are not known. We examined whether the AMPK activator metformin, the PPARγ agonist pioglitazone, or the PPARα agonist WY-14643 could potentiate IFN responses, reverse IFN refractoriness, and enhance viral eradication in hepatocytes. WY-14643 demonstrated the strongest antiviral synergy with IFN-α and so was tested in the context of chronic IFN activation. Cells rendered refractory to IFN by IFN-α pretreatment were resensitized by WY-14643, as demonstrated by improved STAT1 phosphorylation, promoter activation, and ISG expression. WY-14643 treatment reduced the expression of key negative regulators of IFN signaling: the AXL receptor tyrosine kinase, suppressor of cytokine signaling (SOCS) 1 and 3, which are upregulated in the IFN-refractory state. AXL is a novel regulator of IFN-α signaling that is induced by HCV infection in vitro and which may drive SOCS3 expression. Our data suggests that PPARα agonists could be a useful adjunct treatment for chronic HCV infection by reducing the expression of AXL/SOCS and increasing the sensitivity to IFN.

To study the prevalence of impaired glucose tolerance in patients with hepatitis C virus related chronic liver disease

BACKGROUND

Hepatitis C infection is a major cause of Chronic Liver Disease and the prevalence of Diabetes Mellitus is also high. Diabetes has been hypothesised as one of Extrahepatic manifestations of Hepatitis C.

AIMS AND OBJECTIVES

The objective of our study was to study the prevalence of impaired glucose tolerance in patients with HCV related liver disease.

STUDY DESIGN

The study was a prospective study conducted over a period of one and half year in Dayanand Medical College and Hospital, Ludhiana, Punjab, India.

MATERIALS AND METHODS

The study was conducted taking total of 100 Hepatitis C virus positive patients above 40 years of age who had fasting blood glucose levels ≥110mg/dl on two occasions, 24 hours apart. These patients underwent an oral glucose tolerance test. Blood sugar levels were tested at 0 and 2 hours. Based on the findings, patients were classified to have impaired glucose tolerance if levels were between 140-200mg/dl and frank diabetes if the levels were ≥ 200mg/dl. These findings were further assessed according to age, gender, Body Mass Index (BMI) Child Turcott Pugh score and Ultrasonography findings.

STATISTICAL ANALYSIS

In our study all the statistical analysis was done using simple z-test and student t-test. The p-values were calculated and the results assessed accordingly.

RESULTS AND CONCLUSION

Out of 100 patients, 78 were males and rest females. The mean age of the study group was 55.89±11.22 years. Mean BMI of males was higher than in females (21.98kg/m² v/s 20.13kg/m²). Maximum patients belonged to Child Turcott Pugh class C. Out of 100 patients,80 had cirrhosis on ultrasound. On doing Glucose Tolerance Test, 40 patients were found to have impaired glucose tolerance and one patient to be diabetic. The prevalence increased significantly as age increased and had significant relation with gender. On assessing according to BMI, there was not much significant relation but prevalence was significantly related to severity of disease.

Elevated plasma sphingomyelin (d18:1/22:0) is closely related to hepatic steatosis in patients with chronic hepatitis C virus infection

Hepatic steatosis affects disease progression in patients with chronic hepatitis C virus (HCV) infection. We investigated the plasma sphingolipid profile in patients with chronic hepatitis C (CHC) and whether there was an association between HCV-related steatosis and plasma sphingolipids. We used high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze plasma sphingolipids in 120 interferon-naïve, non-diabetic, and non-obese CHC patients. Hepatic steatosis was defined as ≥5 % hepatocytes with fat based on histopathological analysis. Blood biochemical indicators and HCV load and genotype were also determined. Thirty-six (30.0 %) of 120 patients presented with hepatic steatosis Grades 1-3. Forty-four plasma sphingolipids were detected. Plasma sphingomyelin (SM) (d18:1/22:0) and ceramide (Cer) (d18:1/24:0)-1-P correlated with steatosis grade (r = 0.22, p = 0.015; r = -0.23, p = 0.012, respectively). SM (d18:1/22:0) [odds ratio (OR) = 1.12] and Cer (d18:1/24:0)-1-P (OR = 0.88) were independent factors for the presence of hepatic steatosis in CHC patients. The area under the curve (AUC) of SM (d18:1/22:0) and Cer (d18:1/24:0)-1-P was 0.637 and 0.638, respectively, to identify the presence of steatosis. Further analysis for genotype 2 CHC showed that only SM (d18:1/22:0) was independently linked to steatosis (OR = 1.21). The AUC of SM (d18:1/22:0) to identify hepatic steatosis in genotype 2 CHC was 0.726. Its sensitivity and negative predictive value reached 0.813 and 0.886, respectively. This study suggested that altered plasma SM (d18:1/22:0) was closely related to hepatic steatosis in chronic HCV infection, especially with genotype 2. Experimental studies are needed to determine further the underlying mechanisms responsible for these associations.

Body mass index and liver stiffness affect accuracy of ultrasonography in detecting steatosis in patients with chronic hepatitis C virus genotype 1 infection

BACKGROUND & AIMS

Few studies have evaluated the accuracy of ultrasonography in detecting steatosis in patients with chronic hepatitis C. We assessed its accuracy in detecting steatosis and factors that affect its diagnostic performance in consecutive patients with chronic hepatitis C virus genotype 1 infection.

METHODS

We analyzed data from 515 patients with chronic hepatitis C, confirmed by liver biopsy, assessing anthropometric, biochemical, metabolic, virologic, and ultrasonography features. Transient elastography was performed to measure liver stiffness. Steatosis was identified with ultrasonography based on detection of a bright liver echo pattern.

RESULTS

Ultrasonography identified steatosis in 5% or more of parenchyma of the liver with 63.6% sensitivity, 90.4% specificity, an 87.5% positive predictive value (PPV), and a 70.3% negative predictive value (NPV). The higher the degree of steatosis (based on histology analysis), the higher the sensitivity values and NPVs (up to values of 75.3% and 93.8%, respectively, for steatosis in ≥30% of liver), and the lower the specificity values and PPVs (down to values of 69.8% and 31.7% for steatosis in ≥30% of liver, respectively). Body mass index of 30 kg/m(2) or greater (odds ratio, 2.761; 95% confidence interval, 1.156-6.595; P = .02) and liver stiffness measurements of 8.9 kPa or higher (odds ratio, 3.128; 95% confidence interval, 1.715-5.706; P < .001) were independent risk factors for false-negative results from ultrasonography when there was 5% or more steatosis, as well as when there was 10% or more, 20% or more, or 30% or more steatosis.

CONCLUSIONS

Ultrasonography detects steatosis with low levels of accuracy in patients with chronic hepatitis C virus genotype 1 infection; it has low NPVs for amounts of steatosis of 5% or more and low PPVs for livers with moderate-severe amounts. Higher body mass indexes and liver stiffness measurements are associated with false-negative results in steatosis detection by ultrasonography.

A novel fibrosis index comprising a non-cholesterol sterol accurately predicts HCV-related liver cirrhosis

Diagnosis of liver cirrhosis is essential in the management of chronic hepatitis C virus (HCV) infection. Liver biopsy is invasive and thus entails a risk of complications as well as a potential risk of sampling error. Therefore, non-invasive diagnostic tools are preferential. The aim of the present study was to create a model for accurate prediction of liver cirrhosis based on patient characteristics and biomarkers of liver fibrosis, including a panel of non-cholesterol sterols reflecting cholesterol synthesis and absorption and secretion. We evaluated variables with potential predictive significance for liver fibrosis in 278 patients originally included in a multicenter phase III treatment trial for chronic HCV infection. A stepwise multivariate logistic model selection was performed with liver cirrhosis, defined as Ishak fibrosis stage 5–6, as the outcome variable. A new index, referred to as Nordic Liver Index (NoLI) in the paper, was based on the model: Log-odds (predicting cirrhosis) = −12.17+ (age×0.11) + (BMI (kg/m²)×0.23) + (D₇-lathosterol (μg/100 mg cholesterol)×(−0.013)) + (Platelet count (x10⁹/L)×(−0.018)) + (Prothrombin-INR×3.69). The area under the ROC curve (AUROC) for prediction of cirrhosis was 0.91 (95% CI 0.86–0.96). The index was validated in a separate cohort of 83 patients and the AUROC for this cohort was similar (0.90; 95% CI: 0.82–0.98). In conclusion, the new index may complement other methods in diagnosing cirrhosis in patients with chronic HCV infection.

Hepatitis C virus and metabolic disorder interactions towards liver damage and atherosclerosis

Hepatitis C virus (HCV) is one of the main causes of liver disease worldwide, and alterations of glucose metabolism have reached pandemic proportions in western countries. However, the frequent coexistence between these two conditions is more than simply coincidental, since HCV can induce insulin resistance through several mechanisms. Indeed, the virus interferes with insulin signaling both directly and indirectly, inducing the production of pro-inflammatory cytokines. Furthermore, the entire viral life cycle has strict interconnections with lipid metabolism, and HCV is responsible for a “viral” steatosis which is frequently superimposed to a “metabolic” one. Several evidences suggest that HCV-induced metabolic disorders contribute both to the evolution of liver fibrosis and, likely, to the progression of the other disorders which are typically associated with altered metabolism, in particular atherosclerosis. In the present review, we will examine in depth the links between HCV infection and insulin resistance, liver steatosis and diabetes, and analyze the impact of these interactions on the progression of liver fibrosis and atherosclerosis. Special attention will be focused on the highly debated topic of the relationship between HCV infection and cardiovascular disease. The available clinical literature on this item will be broadly reviewed and all the mechanisms possibly implied will be discussed.

Impairment of health-related quality of life in patients with chronic hepatitis C is associated with insulin resistance

BACKGROUND

Although it has been reported that hepatitis C virus (HCV) infection is associated with a significant decline in health-related quality of life (HRQOL), the underlying causes and mechanisms are still unknown. Insulin resistance (IR) is recognized as a distinct aspect of chronic HCV infection. Therefore, we attempted to identify the factors including IR indices that are related to the HRQOL of patients with chronic hepatitis C (CHC).

METHODS

One hundred and seventy-five CHC patients (91 female, 84 male, mean age, 56.4 years) not using antidiabetic agents were included and underwent a 75-g oral glucose tolerance test (OGTT) and completed a self-administered HRQOL questionnaire, the Short Form 36 (SF-36), which is a well-validated questionnaire for assessing general QOL. Scale scores were standardized and summarized into physical and mental component summary (PCS and MCS). We investigated which clinical parameters, including homeostasis model assessment of insulin resistance (HOMA-IR), were associated with decline in PCS and MCS scores in CHC patients.

RESULTS

There were no significant differences in clinical parameters between high and low MCS, but there were significant differences in age, sex, hemoglobin, liver fibrosis, OGTT pattern, and HOMA-IR between high and low PCS. Multivariate analysis showed that HOMA-IR >2 was independently associated with lower PCS (OR 2.92, p < 0.01).

CONCLUSIONS

Our results suggest that impairment of HRQOL, especially physical domains, in CHC patients is associated with IR.

Increased soluble CD36 is linked to advanced steatosis in nonalcoholic fatty liver disease

BACKGROUND

Soluble CD36 (sCD36) clusters with insulin resistance, but no evidence exists on its relationship with hepatic fat content. We determined sCD36 to assess its link to steatosis in nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC) patients.

MATERIALS AND METHODS

Two hundred and twenty-seven NAFLD, eighty-seven CHC, and eighty-five patients with histologically normal liver (NL) were studied. Steatosis was graded by Kleiner's histological scoring system. Serum sCD36 and hepatic CD36 expression was assessed by immunoassay and immunohistochemistry, respectively.

RESULTS

In NAFLD, serum sCD36 levels were significantly higher in simple steatosis than in NL (361.4 ± 286.4 vs. 173.9 ± 137.4 pg/mL, respectively; P < 0.001), but not in steatohepatitis (229.6 ± 202.5 pg/mL; P = 0.153). In CHC, serum sCD36 levels were similar regardless of the absence (428.7 ± 260.3 pg/mL) or presence of steatosis (387.2 ± 283.6 pg/mL; P = 0.173). A progressive increase in serum sCD36 values was found in NAFLD depending on the histological grade of steatosis (P < 0.001), but not in CHC (P = 0.151). Serum sCD36 concentrations were independently associated with advanced steatosis in NAFLD when adjusted by demographic and anthropometric features [odds ratio (OR), 1.001; 95% confidence interval (CI), 1.000 to 1.002; P = 0.021] and by metabolic variables (OR, 1.002; 95% CI, 1.000 to 1.003; P = 0.001). Interestingly, a significant correlation was observed between hepatic CD36 and serum sCD36 (ρ = 0.499, P < 0.001).

CONCLUSIONS

Increased serum sCD36 is an independent factor associated with advanced steatosis in NAFLD.

Metabolic factors and chronic hepatitis C: a complex interplay

In the last years, several lines of evidence showed how metabolic factors may influence the natural history of patients with chronic hepatitis C. Chronic HCV infection is able to perturb the metabolic homeostasis of the host, in a context of complex interactions where pre-existent metabolic status and genetic background play an important role, allowing us to state that HCV infection is a systemic disease. In this review, we discuss the most recent lines of evidence on the main metabolic factors that are known to be associated with CHC, namely, insulin resistance/type 2 diabetes, steatosis, visceral obesity, atherosclerosis, vitamin D, menopause, fructose and coffee intake, lipoproteins, methylenetetrahydrofolate reductase status, and hyperuricaemia. In particular, we focus on the pathophysiological mechanisms underlying the correlation between HCV infection and metabolic disorders, the impact of metabolic factors on the progression of liver and non-liver-related diseases, and, on the contrary, the possible influence of chronic HCV infection on metabolic features. In this setting, the importance of a multifaceted evaluation of CHC patients and a prompt correction of modifiable metabolic risk factors should be emphasized.

Fibrosis evaluation by transient elastography in patients with long-term sustained HCV clearance

BACKGROUND

Reversibility of advanced fibrosis after HCV-clearance is an important goal of therapy.

OBJECTIVES

Measuring liver stiffness (LS) by transient elastography (TE) might be helpful in this setting.

PATIENTS AND METHODS

We evaluated 104 patients with biopsy-proven chronic hepatitis C (CHC) and sustained virological response (SVR) after Peg-Interferon (IFN) plus ribavirin since at least 18 months. HCV-eradication was confirmed searching for serum HCV-RNA (TMA® sensitivity > 5-10 IU/ml). Data from literature reported the best LS cut-off values for different stages of liver fibrosis were 7.1 kPa for Metavir stage 2 (F2), 9.5 kPa for F3 and 12.5 for cirrhosis (F4).

RESULTS

TE was not reliable in four SVR obese patients. Metavir-stage of biopsy was F0-1 in 28, F2 in 47, F3 in 17 and F4 in eight patients. The median interval elapsed since achieving SVR was 36 months (range: 18-77, SD¬¬:18). Stratifying patients according to the histological stage assessed before treatment, a clear-cut gradient of LS values was observed from F0-1: median: 3.8 kPa (range: 3.5-4.9) to F2: 4.6 kPa (3.8-6.0), F3: 6.2 kPa (4.8-8.6) and F4: 8.4 kPa (6.2-9.2) (P = 0.001). Overall, 86 patients had lower values of LS than the expected LS values according to Metavir-stage. At multivariate logistic analysis γ-GT and histological steatosis were independently associated with persistence of higher values of LS.

CONCLUSION

Long term responders to IFN-based therapies have lower LS values than those who are untreated and still viraemic. High levels of γ-GT and liver steatosis, all markers of insulin resistance, may hamper reduction of liver stiffness after HCV-clearance.

High sCD36 plasma level is associated with steatosis and its severity in patients with genotype 1 chronic hepatitis C

Soluble CD36 (sCD36) plasma levels, a known marker of cardiometabolic disorders, are associated with surrogate markers of steatosis, while experimental and human studies show a link between CD36 expression in the liver and steatosis. In a cohort of patients with genotype 1 chronic hepatitis C (G1 CHC), we tested the association of sCD36 plasma levels with host and viral factors and sustained virological response (SVR). One hundred and seventy-five consecutive biopsy-proven patients were studied. sCD36 plasma levels were assessed by an in-house ELISA. All biopsies were scored by one pathologist for staging and grading (Scheuer) and graded for steatosis, which was considered moderate-severe if ≥20%. Patients underwent standard of care therapy with pegylated interferon and ribavirin. The severity of steatosis progressively increased according to sCD36 quartiles (P = 0.02); total and low-density lipoprotein (LDL) cholesterol levels were significantly higher in patients in the lower quartile compared to all the others. Gamma-glutamyl transferase (P = 0.02), homoeostasis model assessment (HOMA) score (P = 0.002) and sCD36 (P = 0.04) were independently associated with the severity of steatosis as continuous variable. Multivariate logistic regression analysis showed that HOMA (OR 1.243, 95% CI 1.04-1.484, P = 0.01) and sCD36 (OR 1.445, 95%CI 1.135-1.839, P = 0.003) were independently linked to steatosis ≥20%. No association was found between sCD36 and SVR. CD36 is linked to steatosis and insulin resistance in patients with G1 CHC, but does not predict response to treatment. The potential of sCD36 as a surrogate marker of steatosis should be further investigated.

Hepatitis C virus diversity and hepatic steatosis

Hepatitis C virus (HCV) infection is closely associated with lipid metabolism defects throughout the viral lifecycle, with hepatic steatosis frequently observed in patients with chronic HCV infection. Hepatic steatosis is most common in patients infected with genotype 3 viruses, possibly due to direct effects of genotype 3 viral proteins. Hepatic steatosis in patients infected with other genotypes is thought to be mostly due to changes in host metabolism, involving insulin resistance in particular. Specific effects of the HCV genotype 3 core proteins have been observed in cellular models in vitro: mechanisms linked with a decrease in microsomal triglyceride transfer protein activity, decreases in the levels of peroxisome proliferator-activating receptors, increases in the levels of sterol regulatory element-binding proteins, and phosphatase and tensin homologue downregulation. Functional differences between the core proteins of genotype 3 viruses and viruses of other genotypes may reflect differences in amino acid sequences. However, bioclinical studies have failed to identify specific 'steatogenic' sequences in HCV isolates from patients with hepatic steatosis. It is therefore difficult to distinguish between viral and metabolic steatosis unambiguously, and host and viral factors are probably involved in both HCV genotype 3 and nongenotype 3 steatosis.

Association of visceral obesity with high viral load and histological findings in elderly patients with genotype 1 chronic hepatitis C

OBJECTIVE

Genotype 1 chronic hepatitis C (G1CHC) is generally accompanied by metabolic disturbances related to visceral obesity, such as insulin resistance, steatosis, or dyslipidemia. Because these abnormalities negatively influence the clinical course of G1CHC, we sought to clarify the effect of visceral obesity on the pathophysiology of G1CHC.

METHODS

We evaluated 180G1CHC patients for the presence of visceral obesity on the basis of computed tomography findings. Multivariate analysis was performed to estimate the relationship between visceral obesity and demographic, viral, and biochemical characteristics of patients. The associations of visceral obesity with histological findings and serum adipokine levels were also analyzed.

RESULTS

Multiple logistic regression analysis revealed that visceral obesity was independently associated with metabolic syndrome, platelet count, high-density lipoprotein level, and serum viral load in elderly patients (≥65 years). Multiple linear regression analysis confirmed the association between visceral obesity and high viral load. However, visceral obesity was not correlated with viral load in non-elderly patients (<65 years). Histological data (160 patients) demonstrated the significant association between visceral obesity and steatosis. Furthermore, patients with visceral obesity showed increase in the severity of fibrosis with advancing age. However, age-associated fibrosis progression was not evident in patients without visceral obesity. The serum adiponectin level was significantly low in patients with visceral obesity, whereas those of leptin, tumor necrosis factor-α, and interleukin-6 were not affected significantly.

CONCLUSION

Visceral obesity was associated with high viral load and histological damage in elderly patients with reduced adiponectin levels.

Serum γ-glutamyl transferase levels, insulin resistance and liver fibrosis in patients with chronic liver diseases

Background and Aims

Serum levels of γ-glutamyl-transpeptidase(γ-GT) were associated with liver disease severity and metabolic alterations, which in turn are able to affect hepatic damage. In patients with nonalcoholic fatty liver disease (NAFLD), genotype 1 chronic hepatitis C (G1CHC) and chronic hepatitis B (CHB), we assessed the link between liver fibrosis and γ-GT serum levels, and we evaluated if normal or high γ-GT serum levels affect the association between insulin resistance (IR) and severity of liver fibrosis.

Methods

843 consecutive patients with chronic liver disease (CLD)(193 NAFLD, 481 G1CHC, 169 CHB) were evaluated by liver biopsy (Kleiner and Scheuer scores) and clinical and metabolic measurements. IR was diagnosed if HOMA>3. A serum γ-GT concentration of >36 IU/L in females and >61 IU/L in males was considered the threshold value for identifying high levels of γ-GT.

Results

By multivariate logistic regression analysis, abnormal γ-GT serum levels were independently linked to severe liver fibrosis in patients with NAFLD (OR2.711,CI1.120–6.564,p = 0.02), G1CHC (OR3.461,CI2.138–5.603,p<0.001) and CHB (OR2.778,CI1.042–7.414,p = 0.04), together with IR and liver necroinflammation, and with a negative predictive value>80%. Interestingly, among patients with high or normal γ-GT values, even if IR prevalence was significantly higher in patients with severe fibrosis compared to those without, IR remained significantly associated with severe fibrosis in patients with abnormal γ-GT values only (OR4.150,CI1.079–15.970,p = 0.03 for NAFLD; OR2.250,CI1.211–4.181,p = 0.01 for G1CHC; OR3.096,CI2.050–34.220,p = 0.01 for CHB).

Conclusions

In patients with CLD, IR is independently linked to liver fibrosis only in patients with abnormal γ-GT values, without differences according to liver disease etiology, and suggesting a role of γ-GT as a marker of metabolic-induced liver damage. These data could be useful for the clinical and pharmacologic management of patients with CLD.

Association of insulin resistance, viral load, and adipokine levels with liver histology in patients with chronic hepatitis C: an observational, multicenter study in Turkey

OBJECTIVE

To evaluate the association of insulin resistance (IR), viral load, and adipokine levels with liver histology in patients with chronic hepatitis C (CHC).

PATIENTS AND METHODS

In this noninterventional, multicenter study carried out at 11 infectious diseases clinics in Turkey, 103 CHC patients [mean (SD) age: 50.2 (11.0) years, 60 (58.3%) women] planned to be treated by ribavirin and peginterferon-α2a were included. Data on hepatic fibrosis and steatosis, IR, viral load, and hepatitis C virus-RNA genotyping, adipokine, and cytokine levels were collected.

RESULTS

The mean (SD) Knodell score was 8.1 (3.6); grade I steatosis was evident in 46 (44.7%) patients and IR was identified in 56 (54.9%). There was a significant positive correlation of the homeostasis model assessment-IR index with Knodell fibrosis (r=0.235; P=0.027) and hepatic steatosis (r=0.435; P<0.001). There was a significant positive correlation of leptin levels with Knodell fibrosis (r=0.265; P=0.013) and hepatic activity index (r=0.218; P=0.041). Hepatic steatosis was correlated negatively with adiponectin (r=-0.320; P=0.001) and positively with leptin (r=-0.368; P<0.001) levels. Logistic regression analysis showed that increase in age [odds ratio (OR), 1.056; 95% confidence interval (CI), 1.005-1.110; P=0.030] was the only significant predictor of hepatic fibrosis (OR, 1.056; 95% CI, 1.005-1.110; P=0.030), whereas increase in age (OR, 1.066; 95% CI, 1.006-1.130; P=0.030), the presence of IR (OR, 5.621; 95% CI, 1.547-20.425; P=0.009), and decrease in adiponectin levels (OR, 0.808; 95% CI, 0.682-0.957; P=0.013) were the significant predictors of hepatic steatosis.

CONCLUSION

Our findings indicate a significant relationship of hepatic fibrosis and hepatic steatosis with IR and leptin levels, but not with the viral load in Turkish patients with CHC.

Hyperuricaemia: another metabolic feature affecting the severity of chronic hepatitis because of HCV infection

BACKGROUND

Several works observed a link between uric acid serum levels and clinical and histological features of nonalcoholic fatty liver disease. An association between chronic hepatitis C (CHC) and uric acid levels has been poorly investigated.

AIMS

To assess the potential association between uric acid serum levels and both histological features of liver damage and sustained virological response (SVR) in a homogeneous cohort of CHC patients.

METHODS

Consecutive biopsy-proven CHC patients were included. Hyperuricaemia was diagnosed with uric acid serum levels >7 mg/dl in men, and >6 mg/dl in women. Patients underwent therapy with pegylated interferon plus ribavirin.

RESULTS

Hyperuricaemia, observed in 7.5% of patients, was associated with low density lipoprotein cholesterol (OR 1.015, 95% CI 1.004-1.026, P = 0.008), arterial hypertension (OR 3.024, 95% CI 1.290-7.088, P = 0.01), estimated glomerular filtration rate (OR 0.942, 95% CI 0.919-0.965, P < 0.001) and severity of steatosis (OR 3.176, 95% CI 1.828-5.517, P < 0.001) by multivariate logistic regression analysis. The following features were independently linked to the severity of liver steatosis (<5% vs. ≥5% to <30% vs. ≥30%) using ordinal regression analysis: age (OR 1.027, 95% CI 1.011-1.044, P = 0.01), body mass index (OR 1.088, 95% CI 1.039-1.138, P < 0.001), triglycerides (OR 1.005, 95% CI 1.001-1.009, P = 0.02), homeostasis model assessment (OR 1.095, 95% CI 1.014-1.184, P = 0.02), hyperuricaemia (OR 2.751, 95% CI 1.423-5.322, P = 0.003), hepatitis C virus genotype 3 (OR 4.567, 95% CI 1.515-13.763, P = 0.007) and severe necroinflammatory activity (OR 1.584, 95% CI 1.067-2.349, P = 0.02). No independent association was found among uric acid levels and necroinflammatory activity, fibrosis and SVR.

CONCLUSIONS

In CHC patients, hyperuricaemia was independently associated with severity of steatosis, representing, in this setting, via steatosis induction, an indirect factor affecting both liver damage and poor response to therapy, and thus a novel potential therapeutic target in CHC management.

Methylenetetrahydrofolate reductase homozygosis and low-density lipoproteins in patients with genotype 1 chronic hepatitis C

Methylenetetrahydrofolate reductase status, homocysteine and lipoproteins levels have been associated with severity of disease and both rapid and sustained virological response (SVR) in patients with genotype 1 chronic hepatitis C (CHC). We aimed to assess the association of homocysteine and MTHFR status with serum cholesterol levels and their potential links to both histological findings and virological response, in patients with genotype 1 hepatitis C virus (HCV). A total of 119 consecutive patients were evaluated by biopsy and metabolic measurements. A total of 103 healthy blood donors were used as controls. Serum homocysteine and MTHFR C677T mutation were also evaluated. All patients underwent antiviral therapy with PEG-IFN alfa-2a plus ribavirin. HCV-RNA was assessed at baseline, week 4, week 12, at the end of therapy and after 6 months of follow-up. Mean serum values of homocysteine were higher in patients than in controls (15.8 ± 5.8 μg/L vs 12.5 ± 5.8 μg/L; P < 0.001), with a similar CC, CT and TT MTHFR distribution (23.6%, 48.7% and 27.7% in G1-CHC vs 34%, 48.5% and 17.5% in controls; P = 0.14). In genotype 1, HCV MTHFR TT homozygosis was independently linked to higher LDL (OR 1.016; CI 1.002-1.031; P = 0.03), but not to homocysteine. No association were found between homocysteine, MTHFR and histological features or both rapid virological response (RVR) and SVR. Low cholesterol (OR 0.988, 95%CI 0.975-0.999, P = 0.04) was independently linked to severe fibrosis, and high LDL was the only independent positive predictors of both RVR and SVR (OR 1.036; 95%CI 1.017-1.055; P < 0.001; and OR 1.016; 95%CI 1.001-1.031; P = 0.04 respectively). In patients with genotype 1 hepatitis C, showing higher homocysteine serum levels than controls, MTHFR C677T homozygosis, via modulating cholesterol levels, could interfere with liver fibrosis and response to antiviral therapy.

Differentially expressed microRNAs in Huh-7 cells expressing HCV core genotypes 3a or 1b: potential functions and downstream pathways

microRNA (miRNA) dysfunction is believed to play important roles in human diseases, including viral infectious diseases. Hepatitis C virus (HCV) infection promotes the development of steatosis, cirrhosis and hepatocellular carcinoma, which is genotype-specific. In order to characterize the miRNA expression profile of Huh-7 cells expressing the HCV core 3a vs. 1b, microarrays and real-time PCR were performed. Consequently, 16 miRNAs (5 miRNAs upregulated and 11 miRNAs downregulated) were found to be dysregulated. In addition, we generated the predicted and validated targets of the differentially expressed miRNAs and explored potential downstream function categories and pathways of target genes using databases of Gene Ontology (GO) and PANTHER and the database for annotation, visualization and integrated discovery (David). The computational results indicated that the dysregulated miRNAs might perform the functions of cellular metabolism and cellular growth. Finally, these biological effects were preliminarily validated. This study identifies a specific miRNA expression profile in cells expressing HCV core proteins of different genotypes (genotype 3a and 1b), which may account for the variable pathophysiological manifestation associated with HCV infection.

Progress in understanding the role of leptin in the pathogenesis and treatment of chronic hepatitis C

Leptin is an adipokine that is abundantly expressed in adipose tissue and has multiple biological effects related to the development of human diseases, such as diabetes mellitus, obesity, metabolism syndrome, and cancer. Pegylated interferon plus ribavirin has been considered as fist-line therapy in patients with chronic hepatitis C (CHC). Because this therapy is associated with many side effects, further studies on the mechanism and treatment of CHC are needed. More and more studies have demonstrated that leptin plays an important role in the pathogenesis of CHC and provides a new target for the treatment of this disease. This paper reviews the recent advances in understanding the role of leptin in the pathogenesis and treatment of CHC.

Autophagy protects cells from HCV-induced defects in lipid metabolism

BACKGROUND & AIMS

Autophagy is a lysosome-mediated catabolic process that mediates degradation and recycling of all major components of eukaryotic cells. Different stresses, including viral and bacterial infection, induce autophagy, which can promote cell survival by removing the stress inducer or by attenuating its dangerous effects. High levels of autophagy occur during infection of cells with hepatitis C virus (HCV), but the clinical relevance of this process is not clear.

METHODS

Levels of autophagy were analyzed in liver biopsy samples from 22 patients with HCV infection using microtubule-associated protein-1 light chain 3 immunoblotting; associations with histological and metabolic parameters were evaluated by Pearson correlation analysis. We investigated the role of HCV-induced autophagy in lipid degradation in cells infected with the virus or replicons, and analyzed autophagosome contents by confocal microscopy and by measuring lipid levels after inhibition of autophagy by Beclin 1 knockdown or lysosome inhibitors.

RESULTS

In liver biopsy samples from patients with HCV, there was an inverse correlation between microvesicular steatosis and level of autophagy (r = -0.617; P = .002). HCV selectively induced autophagy of lipids in virus-infected and replicon cells. In each system, autophagosomes frequently colocalized with lipid deposits, mainly formed by unesterified cholesterol. Inhibition of the autophagic process in these cells significantly increased the induction of cholesterol accumulation by HCV.

CONCLUSIONS

Autophagy counteracts the alterations in lipid metabolism induced by HCV. Disruption of the autophagic process might contribute to development of steatosis in patients with HCV.

Impact of HCV genetic differences on pathobiology of disease

Multiple HCV genotypes have been isolated worldwide. Genotype seems to be involved in the main pathological aspects of HCV infection. Insulin resistance, steatosis and progression toward cirrhosis, fibrosis and hepatocellular carcinoma establish and develop following genotype-specific mechanisms. Moreover genotype influences pharmacological treatment in term of dose and duration. Pathways involved in cell proliferation, apoptosis, lipid metabolism, insulin and interferon signaling are impaired to a different extent among genotypes, leading to distinct pathological settings. Genotype 1 is associated with a more aggressive disease with increased insulin resistance, worst response to therapy, higher risk of cirrhosis and hepatocellular carcinoma development, while genotype 3 is associated with increased steatosis and fibrosis. The identification and characterization of HCV types and subtypes provides insight into the different outcome of HCV infection and responsiveness to therapy. In the present article, we focused on the pathogenicity of HCV genotypes and their effect on disease progression and treatment.

The impact of antiviral therapy and the influence of metabolic cofactors on the outcome of chronic HCV infection

NATURAL HISTORY OF HCV RELATED CHRONIC HEPATITIS IS INFLUENCED AND MODIFIED BY MANY FACTORS: virus features, coinfections and host characteristics. In particular, a peculiar genetic background of the host by conditioning the occurrence of intracellular metabolic derangements (i.e., insulin resistance) might contribute to accelerate the rate of progression to cirrhosis and eventually the occurrence of hepatocellular carcinoma (HCC) and death. Likely, direct interplays between virus genotype and host genetic background might be hypothesized at this level. Morbidity and mortality in cirrhosis is primarily associated with complications of liver cirrhosis (ascites, hepatic encephalopathy, jaundice, and gastroesophageal bleeding) and HCC occurrence. Therefore the main goal of therapy is to clear viral infection and decrease liver necro-inflammation that directly relates to development of cirrhosis and HCC. Among patients treated with Interferon-based therapy, those with sustained viral response showed a significant reduction of progression to cirrhosis and development of HCC. However, a residual risk of hepatocellular carcinoma still remains indicating the need for careful follow-up using ultrasonography every six months in cirrhotic patients, even in those showing persistently normal ALT and undetectable HCV RNA levels after antiviral therapy.

Hepatitis C virus-associated insulin resistance: pathogenic mechanisms and clinical implications

It is now widely recognized that chronic hepatitis C is a metabolic disease, strongly associated with Type 2 diabetic mellitus and insulin resistance (IR). Chronic hepatitis C virus (HCV) infection promotes IR mainly through interfering with the insulin signaling pathway in hepatocytes, increasing the inflammatory response with production of cytokines such as TNF-α and IL-6, and increasing oxidative stress. Accumulated evidence indicates that HCV-associated IR may lead to fibrosis progression, resistance to antiviral therapy, hepatocarcinogenesis and extrahepatic manifestations. Thus, HCV-associated IR is a therapeutic target at any stage of HCV infection. However, specific pharmaceutical treatments of IR are still being evaluated in clinical trials, but available data do not warrant their use in all chronic hepatitis C patients with IR.

Influence of steatosis on progression of fibrosis and virological response in chronic hepatitis C cases

BACKGROUND AND STUDY AIMS

Hepatic steatosis seems to be frequently found histopathologically in chronic hepatitis C virus (HCV)-infected patients. The aim of this study is to determine the influence of steatosis on HCV disease severity (fibrosis) and to evaluate its impact on sustained virological response (SVR) to antiviral therapy.

PATIENTS AND METHODS

From April 2008 to April 2010, 148 consecutive adults (87 females (59%) and 61 males (41%); mean age: 55.2 years) with HCV admitted for liver biopsy were included in this retrospective study. At least one element of metabolic syndrome was identified in all cases: Obesity (n=44), hyperlipidaemia (n=40), hypertension (n=29) and diabetes (n=21). Liver fibrosis was classified according to the Metavir score and hepatic steatosis described as following: S0: absent; S1: minimal (<30%); S2: moderate (30-60%); and S3: severe (>60%). Patients were divided into two groups: S0S1 group (absent or minimal steatosis) and S2S3 group (moderate to severe steatosis). Of the 148 patients, 53 were treated with pegylated interferon and ribavirin combination therapy.

RESULTS

Steatosis was found in 40 patients (27%): S1 in 72.5%, S2 in 17.5% and S3 in 10% of cases. The distribution of patients according to the degree of fibrosis was as follows: in the S0S1 group, F1=12.4%, F2=36.5%, F3=21.1% and F4=21.1% and in the S2S3 group, F1=9%, F2=45.5%, F3=18.2% and F4=27.3%. There was no difference between the two groups regarding the degree of fibrosis (p≥0.80). The rate of SVR was 64%: 63% in the S0S1 group and 75% in the S2S3 group. The difference was not statistically significant (p=1).

CONCLUSION

Steatosis was found in 25% of cases. Liver steatosis in chronic hepatitis C is not a negative prognostic factor of response to combined antiviral therapy. These results must be confirmed by a large series of patients.

'Easy to treat' genotypes were not created equal: can rapid virological response (RVR) level the playing field?

Genotypes 2 and 3 (G2/G3) of hepatitis C virus have been lumped together as 'easy to treat'. As a result, guidelines recommend 24 weeks of peginterferon/ribavirin for both. However, a closer look at trials shows that these genotypes are not the same, with G2 infection proving more responsive to peginterferon. The data supporting this conclusion are presented along with possible explanations for the differences observed. Ultimately, decisions must be made about therapy. Rapid virological response (RVR) may be the best parameter predicting successful antiviral therapy. For patients with G2 infection who achieve an RVR, shortened courses of therapy are effective. In contrast, for G3 patients without an RVR, there may be benefit to extending therapy to 48 weeks; however, this requires confirmation in prospective studies. Using RVR to guide therapy may level the playing field between these 'easy to treat' genotypes.

Meta-analysis: insulin resistance and sustained virological response in hepatitis C

BACKGROUND

A higher baseline homeostasis model assessment of insulin resistance (HOMA-IR) score has sometimes predicted a poorer sustained virological response (SVR) rate to peginterferon/ribavirin therapy in treatment-naïve chronic hepatitis C patients.

AIM

To perform a meta-analysis to evaluate the impact of HOMA-IR on SVR in hepatitis C.

METHODS

Relevant studies were identified by searching Medline and EMBASE. We identified 17 publications that addressed the influence of insulin resistance on SVR. The random effect model of Der Simonian and Laird method were used for heterogeneous studies using the Meta-Disc software 1.4, Madrid, Spain.

RESULTS

Normal insulin sensitivity was associated with a higher rate of SVR [odds ratio (OR) 2.86 (95%CI: 1.97-4.16)] in comparison with insulin resistance. Moreover, in separate analysis by genotype selecting studies that used HOMA-IR > 2 as cut-off defining insulin resistance, SVR was higher in patients with HOMA-IR < 2 in all genotypes: HCV-1 [OR: 2.16 (95%CI: 1.51-3.08)], HCV-2&3 [OR: 3.06 (95%CI: 1.06-8.82)] and HCV-4 [OR: 6.65(95%CI: 2.51-17.61)]. Studies reporting no association between HOMA and SVR included easy-to-cure cohorts, analysed variables strongly related with insulin resistance like body mass index, steatosis, hyper γGT, age and fibrosis and reported differences in handling and interpretation of HOMA-IR.

CONCLUSION

Elevated HOMA-IR was associated with a lower cure rate of patients with hepatitis C treated with Peg-IFN-α/ribavirin irrespective of genotype, and the more difficult-to-treat cohort, the better the HOMA-IR prediction. HOMA-IR is, as a surrogate marker of insulin resistance, susceptible to some biases derived from both handling and interpretation.

The HIV/HCV-coinfected patient and new treatment options

Hepatitis C (HCV) treatment is on the cusp of change with the approval of the first direct-acting antivirals: telaprevir and boceprevir. Drug-drug interactions with HIV antiretrovirals, increased toxicity, and rapid selection of HCV-resistant mutants are among the treatment complexities expected in this difficult-to-treat population. Until the current standard of care changes, focus should be on strategies to optimize management of HIV/HCV-coinfected patients with currently available options. This article reviews the latest predictive factors of response to HCV treatment with the current standard of care in HIV-coinfected patients, and new treatment options.

High liver RBP4 protein content is associated with histological features in patients with genotype 1 chronic hepatitis C and with nonalcoholic steatohepatitis

BACKGROUND AND AIM

To investigate the hepatic expression of retinol-binding protein-4 (RBP4) in chronic hepatitis C (CHC) and nonalcoholic steatohepatitis (NASH) patients, and its association with biochemical and histological patterns of liver damage.

MATERIALS AND METHODS

Sixty-six genotype 1 CHC and 32 NASH patients were tested for hepatic RBP4 expression. Liver expression at immunostaining was scored as 0 (slight), 1 (mild), 2 (moderate), and 3 (intense). In addition, the mRNA and the quantitative protein expressions of RBP4 were tested by PCR and by western blot, respectively, in 12 NASH and 28 CHC patients. Twelve subjects undergoing elective cholecystectomy served as controls.

RESULTS

Ten (31%), 16 (50%) and 6 (19%) NASH patients, and 21 (32%), 31 (47%) and 14 (21%) CHC patients had scores of 1, 2 and 3, respectively. All control subjects scored 0. In both CHC and NASH liver RBP4 scores were directly related to western blot (p=0.001 and p=0.03), not to mRNA expression (p=0.77 and p=0.40). Older age (OR, 1.07; 95%CI, 1.01-1.13), RBP4 score (4.26; 1.27-14.21) and HOMA (2.26; 1.15-4.42) were independently associated with steatosis≥10% in CHC patients. In NASH lobular inflammation (OR, 3.77; 95%CI, 1.01-24.22) and RBP4 score (4.87; 1.003-23.65) were the only risk factors for fibrosis ≥2 at logistic regression analysis.

CONCLUSION

Hepatic storage of RBP4, unrelated to its expression, could cause liver damage both in NASH and CHC.

Hepatic steatosis and insulin resistance are associated with severe fibrosis in patients with chronic hepatitis caused by HBV or HCV infection

BACKGROUND AND AIMS

Steatosis and insulin resistance (IR) are the major disease modifying in patients with chronic hepatitis C (CHC). Only few studies evaluated these features in patients with chronic hepatitis B (CHB). We aimed to assess the prevalence and the factors related to steatosis and IR in CHB patients, compared with CHC subjects, and to evaluate the potential association between these features and fibrosis severity.

MATERIAL AND METHODS

One hundred and seventy consecutive patients with CHB (28 HBeAg positive, 142 HBeAg negative), were evaluated using liver biopsy and metabolic measurements and matched for sex, age and body mass index with 170 genotype 1 CHC patients. IR was defined if HOMA-IR>2.7. All biopsies were scored for grading and staging by Scheuer's score, and the steatosis was considered significant if ≥ 10%.

RESULTS

The prevalence of significant steatosis was similar in both CHB and CHC patients (31 vs. 38%; P=0.14). IR rate was significantly higher in CHC than in CHB patients (42 vs. 26%; P=0.002). Severe fibrosis (F3-F4), at multivariate analysis, was independently associated with older age (OR 1.050, 95% CI 1.009-1.093), steatosis >10% (OR 4.375, 95% CI 1.749-10.943), and moderate-severe necroinflammatory activity (OR 8.187, 95% CI 2.103-31.875), regardless of HBeAg status, in CHB patients, and with older age (OR 1.080, 95% CI 1.028-1.136), IR (OR 2.640, 95% CI 1.110-6.281), steatosis >10% (OR 3.375, 95% CI 1.394-8.171), and moderate-severe necroinflammatory activity (OR 8.988, 95% CI 1.853-43.593) in CHC patients.

CONCLUSIONS

CHB patients had high steatosis prevalence, similar to CHC controls, but lower IR rate. Both steatosis and IR in CHC, and only steatosis in CHB, are independently associated with fibrosis severity.

Metabolic factors are associated with serum alanine aminotransferase levels in patients with chronic hepatitis C

BACKGROUND

Although serum alanine aminotransferase (ALT) activity is an important marker for the management of chronic hepatitis C (CHC), the factors associated with serum ALT levels remain to be fully understood. This study aimed to clarify the association between serum ALT levels and clinical, histological, and virological factors in patients with CHC.

METHODS

We retrospectively analyzed 256 patients with CHC who underwent liver biopsy, and classified them into three groups according to serum ALT levels: normal to minimal (<40 IU/L), mild (40-80 IU/L), and moderate to severe elevation (≥80 IU/L). All demographic and laboratory data were collected at the time of liver biopsy. All biopsies were evaluated for fibrosis, inflammation, and steatosis. Glucose metabolism was assessed by various indices derived from oral glucose tolerance tests, including the homeostasis model assessment for insulin resistance (HOMA-IR). In 180 patients, visceral fat area was measured at the umbilical level by abdominal computed tomography.

RESULTS

Ordered logistic regression analysis showed that higher serum ALT levels were significantly associated with male sex, lower high-density lipoprotein cholesterol (HDL-C), higher HOMA-IR, and higher grades of histological inflammation and steatosis. HOMA-IR, HDL-C, and hepatic steatosis were associated with visceral fat accumulation.

CONCLUSIONS

Metabolic factors, as well as sex and hepatic inflammation, are independent risk factors for serum ALT elevation in hepatitis C virus (HCV)-infected patients. Metabolic factors may offer targets to decrease serum ALT levels.

The homeostasis model assessment of the insulin resistance score is not predictive of a sustained virological response in chronic hepatitis C patients

OBJECTIVES

To investigate the independent association between the homeostasis model assessment of the insulin resistance (HOMA-IR) score and rapid virological response (RVR) and sustained virological response (SVR) in chronic hepatitis C (CHC).

METHODS

Observational prospective cohort study of 412 CHC patients [59% males; mean age 45 years; genotype 1 (44%), 2 (32%), 3 (19%) and 4 (5%)] treated with pegylated interferon α plus ribavirin.

RESULTS

A HOMA-IR ≥2.0 was present in 49% and a metabolic syndrome in 4% of patients. By multivariate analysis, independent predictors of SVR were the lack of advanced fibrosis (≥F3) in genotype 1 and a lower body mass index in genotype 3 patients. In the subgroup of patients in whom HCV-RNA was evaluated at week 4 (n = 281), independent predictors of RVR were HCV-RNA <700,000 IU/ml, age <40 years and lower aspartate aminotransferase:alanine aminotransferase ratio in genotype 1 and baseline HOMA-IR ≤2 in genotype 3 patients. No predictive factor of RVR was identified among genotype 2 patients. RVR was the strongest predictor of SVR among genotype 1 or 3 patients.

CONCLUSIONS

In this series of treatment-naïve, Caucasian CHC patients at a low risk for the metabolic syndrome, HOMA-IR is not a predictor of SVR, irrespective of the HCV genotype, although it may predict RVR in genotype 3 infection.

Insulin resistance predicts re-treatment failure in an efficacy study of peginterferon-α-2a and ribavirin in HIV/HCV co-infected patients

BACKGROUND & AIMS

Few studies evaluated the efficacy of HCV re-treatment and the predictors of response in HIV/HCV co-infected patients. The role of insulin resistance as a predictor of response in this population is unknown. The aim of this study is to evaluate the safety and efficacy of pegylated interferon-α-2a and ribavirin in re-treatment of HIV/HCV co-infected patients, predictors of sustained virological response, including insulin resistance, and the relationship between insulin resistance and liver histology.

METHODS

This prospective, multi-centered study included HIV/HCV co-infected patients with prior interferon-based treatment failure. Patients received pegylated interferon-α-2a and ribavirin for 48 weeks. Serum HCV RNA was measured 24 weeks post treatment to assess sustained virological response. Insulin resistance was defined as HOMA-IR >2. Correlations between baseline insulin resistance and steatosis, and/or cirrhosis were determined.

RESULTS

Sustained virological response was achieved in 14/96 (15%) patients. 35% of patients with HOMA-IR < 2 (6/17) achieved sustained virological response vs 14% (5/36) of those with HOMA-IR between 2-4, and 7% (3/41) of those with HOMA-IR > 4 (p = 0.01). In multivariable analysis, insulin resistance and log₁₀ HCV RNA were negatively associated with sustained virological response [AOR 0.17; 95% CI 0.05-0.64, p = 0.009, and AOR 0.36; 95% CI 0.14-0.93, p = 0.04, respectively]. Steatosis and cirrhosis correlated with insulin resistance (p = 0.02 and 0.03, respectively) but neither independently predicted sustained virological response. Discontinuations due to severe adverse events occurred in 8% of cases, and 2 patients died of unrelated causes.

CONCLUSIONS

In HIV/HCV co-infected patients undergoing re-treatment, sustained virological response rate is low; those patients without insulin resistance are significantly more likely to achieve sustained virological response.

Insulin resistance, steatosis, and fibrosis in Egyptian patients with chronic Hepatitis C virus infection

BACKGROUND/AIM

Both nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C virus (HCV) infection are common in Egypt, and their coexistence is expected. There is controversy regarding the influence of NAFLD on chronic HCV disease progression. This study evaluates the effect of NAFLD on the severity of chronic hepatitis C (CHC) (necroinflammation and fibrosis) and assesses the relative contribution of insulin resistance syndrome to the occurrence of NAFLD in patients with chronic HCV infection.

PATIENTS AND METHODS

Untreated consecutive adults with chronic HCV infection admitted for liver biopsy were included in this study. Before liver biopsy, a questionnaire for risk factors was completed prospectively, and a blood sample was obtained for laboratory analysis.

RESULTS

Our study included 92 male patients. Their mean ± SD age and aspartate aminotransferase (AST) level were 42 ± 7.7 years (range 20-56) and 68 ± 41.7 U/L (range 16-214), respectively. The mean insulin level and insulin resistance index were 15.6 ± 18.3 mIU/mL (range 5.1-137.4) and 5.9 ± 15.2 (range 0.9-136.2), respectively. Fifty four percent of patients had steatosis and 65% had fibrosis. In multivariate analyses, steatosis was associated with insulin resistance and fibrosis was associated with high AST level, age ≥40 years, and steatosis.

CONCLUSIONS

Steatosis is a histopathologic feature in >50% of patients with chronic HCV infection. Insulin resistance has an important role in the pathogenesis of steatosis, which represents a significant determinant of fibrosis together with high serum AST level and older age.

Visceral adiposity index is associated with histological findings and high viral load in patients with chronic hepatitis C due to genotype 1

Metabolic factors have been associated with liver damage in patients with genotype 1 chronic hepatitis C (G1 CHC). We tested visceral adiposity index (VAI), a new marker of adipose dysfunction in G1 CHC, patients to assess its association with host and viral factors and its link to both histological findings and sustained virological response (SVR). Two hundred thirty-six consecutive G1 CHC patients were evaluated by way of liver biopsy and anthropometric and metabolic measurements, including insulin resistance (IR), homeostasis model assessment (HOMA), and VAI using waist circumference, body mass index, triglycerides, and high-density lipoprotein cholesterol. All biopsies were scored by one pathologist for staging and grading and graded for steatosis, which was considered moderate to severe if ≥ 30%. Multiple linear regression analysis revealed that VAI score was independently associated with higher HOMA score (P = 0.009), log10 hepatitis C virus RNA levels (P = 0.01), necroinflammatory activity (P = 0.04), and steatosis (P = 0.04). Multiple logistic regression analysis revealed that IR (OR 3.879, 95% CI 1.727-8.713, P = 0.001), higher VAI score (OR 1.472, 95% CI 1.051-2.062, P = 0.02), and fibrosis (OR 2.255, 95% CI 1.349-3.768, P = 0.002) were linked to steatosis ≥ 30%. Logistic regression analysis revealed that older age (OR 1.030, 95% CI 1.002-1.059, P = 0.03), higher VAI score (OR 1.618, 95% CI 1.001-2.617, P = 0.04), and fibrosis (OR 2.608, 95% CI 1.565-4.345, P < 0.001) were independently associated with moderate to severe necroinflammatory activity. No independent associations were found between VAI score and both fibrosis and SVR.

CONCLUSION

In G1 CHC patients, higher VAI score is independently associated with both steatosis and necroinflammatory activity and has a direct correlation with viral load.

Chemerin, vaspin and insulin resistance in chronic hepatitis C

Adipocytokine profile seems to play a distinct role in the pathogenesis of chronic hepatitis C (CHC). Chemerin and vaspin are recently described adipocytokines with various suggested functions and potential to modulate inflammatory response and insulin resistance (IR). We assessed chemerin, vaspin and leptin serum concentration and studied their association with IR laboratory and morphological features in patients with hepatitis C. The study included 40 patients with hepatitis C and 20 healthy volunteers, similar in age and body mass index (43.6 +/- 11.6 vs 40.9 +/- 11.8 years and 25.0 +/- 4.1 vs 23.9 +/- 3.3 kg/m(2), respectively). Patients had to have a normal lipid profile, and diabetes was an exclusion criteria. Serum chemerin and leptin levels and IR were significantly higher in patients with hepatitis C when compared to the controls (P = 0.02, P = 0.02 and P = 0.02, respectively), whereas vaspin level was significantly decreased (P = 0.01). Serum chemerin was negatively associated with necro-inflammatory grade (r = (-0.49), P = 0.01). The lowest levels of serum chemerin were found in patients with moderate/severe inflammation (P = 0.03). Serum leptin tended to be up-regulated in patients with minimal inflammatory activity. Serum vaspin was higher, although not significantly, when fibrosis was more advanced. IR was positively associated with fibrosis stage (r = 0.33, P = 0.03). Serum chemerin and leptin were related to each other (r = 0.45, P = 0.02).Our findings support a complex interaction between the analysed adipokines and pathogenesis of inflammatory process in CHC. The role of chemerin and vaspin in pathogenesis of inflammatory response should be further investigated.

Hepatic ISG expression is associated with genetic variation in interleukin 28B and the outcome of IFN therapy for chronic hepatitis C

BACKGROUND & AIMS

Multiple viral and host factors are related to the treatment response to pegylated-interferon and ribavirin combination therapy; however, the clinical relevance and relationship of these factors have not yet been fully evaluated.

METHODS

We studied 168 patients with chronic hepatitis C who received pegylated-interferon and ribavirin combination therapy. Gene expression profiles in the livers of 91 patients were analyzed using an Affymetrix genechip (Affymetrix, Santa Clara, CA). The expression of interferon-stimulated genes (ISGs) was evaluated in all samples by real-time polymerase chain reaction. Genetic variation in interleukin 28B (IL28B; rs8099917) was determined in 91 patients.

RESULTS

Gene expression profiling of the liver differentiated patients into 2 groups: patients with up-regulated ISGs and patients with down-regulated ISGs. A high proportion of patients with no response to treatment was found in the up-regulated ISGs group (P=.002). Multivariate logistic regression analysis showed that ISGs (<3.5) (odds ratio [OR], 16.2; P<.001), fibrosis stage (F1-F2) (OR, 4.18; P=.003), and ISDR mutation (>or=2) (OR, 5.09; P=.003) were strongly associated with the viral response. The IL28B polymorphism of 91 patients showed that 66% were major homozygotes (TT), 30% were heterozygotes (TG), and 4% were minor homozygotes (GG). Interestingly, hepatic ISGs were associated with the IL28B polymorphism (OR, 18.1; P<.001), and its expression was significantly higher in patients with the minor genotype (TG or GG) than in those with the major genotype (TT).

CONCLUSIONS

The expression of hepatic ISGs is strongly associated with treatment response and genetic variation of IL28B. The differential role of host and viral factors as predicting factors may also be present.

Toll-like receptor 9 promotes steatohepatitis by induction of interleukin-1beta in mice

BACKGROUND & AIMS

Development of nonalcoholic steatohepatitis (NASH) involves the innate immune system and is mediated by Kupffer cells and hepatic stellate cells (HSCs). Toll-like receptor 9 (TLR9) is a pattern recognition receptor that recognizes bacteria-derived cytosine phosphate guanine (CpG)-containing DNA and activates innate immunity. We investigated the role of TLR9 signaling and the inflammatory cytokine interleukin-1beta (IL-1beta) in steatohepatitis, fibrosis, and insulin resistance.

METHODS

Wild-type (WT), TLR9(-/-), IL-1 receptor (IL-1R)(-/-), and MyD88(-/-) mice were fed a choline-deficient amino acid-defined (CDAA) diet for 22 weeks and then assessed for steatohepatitis, fibrosis, and insulin resistance. Lipid accumulation and cell death were assessed in isolated hepatocytes. Kupffer cells and HSCs were isolated to assess inflammatory and fibrogenic responses, respectively.

RESULTS

The CDAA diet induced NASH in WT mice, characterized by steatosis, inflammation, fibrosis, and insulin resistance. TLR9(-/-) mice showed less steatohepatitis and liver fibrosis than WT mice. Among inflammatory cytokines, IL-1beta production was suppressed in TLR9(-/-) mice. Kupffer cells produced IL-1beta in response to CpG oligodeoxynucleotide. IL-1beta but not CpG-oligodeoxynucleotides, increased lipid accumulation in hepatocytes. Lipid accumulation in hepatocytes led to nuclear factor-kappaB inactivation, resulting in cell death in response to IL-1beta. IL-1beta induced fibrogenic responses in HSCs, including secretion of tissue inhibitor of metalloproteinase-1. IL-1R(-/-) mice had reduced steatohepatitis and fibrosis, compared with WT mice. Mice deficient in MyD88, an adaptor molecule for TLR9 and IL-1R signaling, also had reduced steatohepatitis and fibrosis. TLR9(-/-), IL-1R(-/-), and MyD88(-/-) mice had less insulin resistance than WT mice on the CDAA diet.

CONCLUSIONS

In a mouse model of NASH, TLR9 signaling induces production of IL-1beta by Kupffer cells, leading to steatosis, inflammation, and fibrosis.